Diamond has been known to people for a very long time.
The first diamond was discovered in 4
millennium BC in India.
Even then, diamonds were attributed
magical action, so their
often used as talismans.
Diamonds were also famous and very
appreciated by the ancient Romans. So
as it was believed that after cutting
the diamond loses its magical power,
therefore, until 1910 mass
virtually no diamond processing
existed.
application in many industries
industry and jewelry
art. But natural diamonds are rare
and roads. Their annual production
is several million carats.
And most of them are used for
technological needs as diamond
dust is an excellent abrasive.
Therefore, the idea of creating artificial
diamonds for a very long time worried the minds
scientists. First attempt to create
artificial diamond made
fluorine discoverer Henri
Moisson. He reported that
he managed to get
diamonds the size of
pin head,
dissolving coal
powder in iron at 3000°
and cooling the melt
lead. However, no one
was able to successfully replicate
Moisson's experience. decisive step for
discoveries of artificial
diamond made
Soviet scientist Ovsei
Ilyich Lepunsky. it
he made a discovery
being in disgrace
Soviet
government, due to
his brother's arrest.
Then Ovsei Ilyich
began to earn an article
mi for magazines. One
from reviews - by
prospects for synthesis
diamond - was ordered
magazine "Knowledge is power". Ovsey became
calculate the phase
carbon chart
graphite-diamond systems. Leipunsky identifies three conditions for
formation of diamond from graphite:
1. Temperature 1500 -2500 C
2. .Pressure 60 - 80 thousand atmospheres
3. The presence of iron in carbon and
some other metals that
dissolve carbon and it is lighter
crystallizes. The first artificial
diamonds Turning graphite into diamond is incredibly difficult
a task. Designed special installations and
devices capable of creating and withstanding
high pressures and temperatures. Simultaneously
solved many other complex scientific and
engineering problems. In all this, a big
merit of the team of scientists of the Institute of High
pressure under the guidance of Academician L.F.
Vereshchagin and the Institute of Synthetic
superhard materials and tools under
the leadership of V. N. Bakul. Turning graphite into diamond is incredible
difficult task. Designed special
installations and apparatus capable of creating and
withstand high pressures and temperatures.
At the same time, many other
complex scientific and engineering problems. In
all this is a great merit of the team of scientists
Institute for High Pressures under the direction of
Academician L. F. Vereshchagin and the Institute
synthetic superhard materials and
instruments under the direction of V. N. Bakul. V. N. Bakul
L.F. Vereshchagin installation diagram for receiving
artificial diamonds
This is a scheme of an installation for obtaining artificial diamonds. First, after the cylinder is installed in the high pressure press, water is supplied and
This is a scheme of an installation for obtaining artificial diamonds. First, after installing the cylinder in the presshigh pressure, water is supplied and the graphite is pre-compressed by pressure
water, up to about 2-3 thousand atmospheres. In the second stage, the refrigerant is supplied and the water is frozen until
temperatures minus 12 degrees Celsius. In this case, there is an additional compression of graphite up to 20
thousand atmospheres due to the expansion of ice. At the next stage, a powerful impulse is given
electric current for 0.3 seconds. At the final stage, the ice is thawed and
take out diamonds. Diamonds obtained in this way are mostly dirty in color, have a porous
structure, the shape of the crystals is tetrahedral. Mostly stronger than natural diamonds and
mainly serve for technical purposes.
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The presentation on the topic "Diamonds" can be downloaded absolutely free of charge on our website. Project subject: Chemistry. Colorful slides and illustrations will help you keep your classmates or audience interested. To view the content, use the player, or if you want to download the report, click on the appropriate text under the player. The presentation contains 10 slide(s).
Presentation slides
slide 1
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diamonds
Nature classically produces a diamond in the form of an octahedron (octahedron). Once cut, a diamond is called a diamond. The value of diamonds is determined by the rule of four "K": 1. Carat (measure of weight - 0.2 g). 2. "Clarity" (transparency or purity). 3. Color (color). 4. "Kat" (cutting). Diamonds are most often colorless, but there are exceptions. The famous "Orlov" weighing 195 carats - dark brown, mysteriously disappeared at the beginning of the century "Fiorentino" weighing 137 carats - golden yellow. Red diamonds are highly valued, of which there are only 5 in the world.
slide 3
Secrets of diamonds
1. Only 1% of all cut diamonds are over 1 carat. 2. The world's largest diamond "Cullinan", mined in South Africa, had a weight of 3106 carats. It was bought by the government of the Transvaal and presented to Edward VII. He ordered the stone to be sawn, and from the largest piece they received the diamond "Star of Africa". 3. The average world price for one carat of a diamond is 500 German marks. You should not buy diamonds from your hands, since there is a very high probability of fraud: they can sell you zircon, beryl, colorless topaz. 4. Royal diamond On December 18, 1991, the famous Israeli jewelry king Zvi Yehuda presented Russia with a unique black diamond weighing 21.18 carats. This is already the second black diamond in the collection of the Kremlin Diamond Fund. It is believed that this is the first polished diamond in Russia, made between 1830-1840. at the Makarov factory in St. Petersburg. Nicholas I gave the diamond to one of Zvi's ancestors as a token of gratitude for the agreement that linked the royal court with the Rothschild house in Frankfurt.
slide 4
Kohinoor (Mountain of Light)
The legendary diamond, the first mention of which dates back to 1304. There is a belief that once this stone was set in the throne of Shah Jehan as a peacock eye. According to legend, the age of this unique gem is equal to the age of the ancient Indian hero Vikramaditya, that is, it is counted from 56 BC. But the history of the diamond can be traced more reliably only from the 12th century. According to the records of "Babur-name" by Sultan Babur (1483-1530), the diamond found itself in the treasury of Delhi after the conquest by Sultan Ala-Addin Khilji in 1304 of the principality of Malwa, where for several centuries it was the family jewel of the Rajas. The founder of the Great Mogul dynasties and the Muslim empire in India, the great-grandson of Timur, Babur, in 1526 became the ruler of Hindustan. It is known from his notes that among the numerous treasures he brought as a tribute to his heir - son Hamayun, there was also a large diamond. According to another legend, the diamond was the property of the Raja of the Principality of Gwalior, who presented the stone to Padishah Gamayun. However, of the eighteen owners of this diamond, some were treacherously killed, some fell in battles, and the survivors were expelled and died in poverty. In the Middle Ages, it was said to be worth "half the cost of the whole world." The stone belonged in turn to many monarchs in India and Persia, was often stolen, but was never bought or sold. Oval shaped diamond. After the first somewhat rough cut, it weighed 186.1 carats. It was presented by the Indian Maharajas in 1849 to the English Queen Victoria. It seemed dull to her, and in 1852 the stone was cut again. As a result, the weight of the diamond decreased to 108.93 carats. Now weighs 105.6 carats. Belongs to the British royal family.
slide 5
Great Star of Africa
The largest diamond in the world. Obtained from the famous Culinan diamond, which was the largest ever found on our planet. At the time of its discovery in 1905 at the Premier mine in South Africa, the diamond was the size of a large man's fist and weighed 3,106 carats (more than 600 grams). The government of the Transvaal Republic bought Culinan and presented it to the English king Edward VII for his birthday. The diamond was cut by the famous Amsterdam master Joseph Asher. When split, Kulinan broke up into 9 large stones and 96 fragments. The "Great Star of Africa" is the heaviest of them all. It weighs 530.20 carats, has 74 facets and is set in the royal scepter. The second - "Small Star of Africa" (317 carats), mounted on the imperial crown. Those who were lucky enough to see Queen Elizabeth II with all the regalia could observe both of these extraordinary diamonds.
slide 6
Idol eye
A flat pear-shaped stone about the size of a chicken egg. When cut, it weighs 70.2 carats. According to legend, he served as the second eye of the Lord in the temple of Srirangen and was also stolen. Legend has it that he came to the Shah of Kashmir, who gave him to the Turkish Sultan as a ransom for the kidnapped princess.
Slide 7
The legendary diamond was found in 1701 by a slave prospector near Golconda, India. Raw weighed 410 carats. One of its first owners was British Prime Minister William Peet. The cushion cut of this diamond weighs 140.5 carats. Until the sale in 1717 to the Duke of Orleans, the diamond was named Pete. In honor of the Duke, who was the regent of the young Louis XV, he received the name "Regent". Later, the diamond adorned the crown in which Louis was crowned. After the French Revolution, the diamond belonged to Napoleon Bonaparte, who fixed it in the hilt of his sword. The Regent is currently on display at the Louvre.
Slide 8
A pear-shaped diamond weighing 55.23 carats, famous not only for its unique beauty, but also for its incredibly intricate history. It was named after its first known owner, Nicola Harley de Sancy, who was erroneously believed to be the French ambassador to Turkey. In fact, he was a member of the French Parliament and close associate of King Henry III. When Heinrich became bald, he borrowed his diamond from Sancy and wore it on his beret. In 1605, Sancy sold the diamond to the English King James I. In the middle of the 17th century, "Sancy" came to Cardinal Mazarin, and after his death, along with the entire cardinal's diamond collection, it was inherited by the Bourbons. During the French Revolution, the diamond was sold by the Convention for 1 million francs to a Spanish marquis. In 1828 "Sancy" was bought by Nikolai Demidov, a representative of the family of famous Ural breeders, who was the husband of Princess Matilda, daughter of Napoleon's brother - Jerome Bonaparte, King of Westphalia. At the end of the 19th century, "Sancy" was bought from the heirs of Nikolai Demidov by an American diplomat, and later by a British nobleman, William Astor. In 1978, the fourth-generation Astor sold the diamond to the French National Museum.
Slide 9
Hydrangea
Unique peach color diamond weighing 20 carats. Named after the Dutch Queen Hortense de Beaharnis, who was the daughter of Josephine and adopted daughter of Napoleon Bonaparte. Since the time of Louis XIV, the Hortensia diamond has belonged to the French royal family. Now on display at the Louvre.
Slide 10
How to distinguish a diamond from a fake and imitation:
1. You have an imitation in your hands if there are scratches on the stone after you run sandpaper over it, while you won’t make scratches on a diamond. 2. If the stone warms up, if you hold it a little in the palm of your hand, then this is not a diamond. A diamond is always cold. 3. Breathe on a stone: if it "fogs" and it takes some time until it regains its initial transparency - this is not a diamond, it does not "sweat". 4. Draw a straight line on a white sheet of paper, put a diamond on it: if the image of the line does not curve, it is a fake. A real diamond will definitely "break" the line. 5. If you throw a diamond into a glass of water, it becomes invisible, and an ordinary stone will be immediately visible. 6. The most reliable way to appraise a diamond is to show it to a specialist from one of the Skarbnitsa pawnshops.
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Diamond Diamond is a mineral, a cubic allotropic form of carbon. Under normal conditions, it is metastable, that is, it can exist indefinitely. In a vacuum or in an inert gas at elevated temperatures, it gradually transforms into graphite.slide 2
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Diamond mining There are three ways to organize the extraction of diamond ore: - in diamond pits (in deposits where the rock lies close to the surface and can be extracted by an open method, in fact a large hole) - in underground mines (in deposits where diamond ore lies deep from surface, you have to drill vertical diamond mines and go down inside) - in diamond mines (combined method) Diamond mines
slide 4
Diamond deposits In Russia: Yakutia, Krasnovishersky district of the Perm Territory, Arkhangelsk region, Mezensky district. There are also large diamond deposits in Africa.
slide 5
The structure of the system is cubic, the crystal lattice is face-centered cubic, a = 0.357 nm = 3.57 Å, z = 4, space group Fd3m (according to Hermann - Mogen). The carbon atoms in diamond are in a state of sp³-hybridization. Each carbon atom in the diamond structure is located in the center of a tetrahedron, the vertices of which are the four nearest atoms. It is the strong bond of carbon atoms that explains the high hardness of diamond.
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Physical and mechanical properties Diamond is the hardest mineral, but at the same time brittleness, the highest thermal conductivity, refracts light. Diamond is a dielectric. Unit cell of diamond
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Diagnosis of a diamond In order to distinguish a real diamond from its imitation, a special “diamond probe” is used to measure the thermal conductivity of the examined stone. Diamond has a much higher thermal conductivity value than its substitutes. In addition, the good wettability of the diamond with grease is used: a felt-tip pen filled with special ink leaves a solid line on the surface of the diamond, while on the imitation surface it crumbles into separate droplets.
Slide 9
The use of diamonds Jewels - diamond Used for the manufacture of knives, drills, cutters, and so on. Also used in quantum computers, in the watch and nuclear industries. In 2004, for the first time, a diamond was synthesized at the IHPP RAS, which has a superconducting transition at a temperature of 2-5 K.
slide 10
Top 10 Most Famous Diamonds The Great Mogul Diamond was named after Shah Jahan, the Mughal ruler who built the Taj Mahal.
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Top 10 Most Famous Diamonds The Cullinan I diamond was the largest diamond in the world until the Golden Jubilee was unveiled. It was made from a fragment of the largest diamond in history - the Cullinan diamond weighing 3106 carats. The diamond, which is also called the Great Star of Africa, was found on January 26, 1905 in South Africa. It was named after the owner of the mine, Thomas Cullinan.
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Top 10 Most Famous Diamonds The Golden Jubilee Diamond The Golden Jubilee is the largest cut diamond in the world. The golden-brown diamond replaced the Great Star of Africa and was discovered in 1980 in the Premier mine. For a long time he remained unnoticed, and he was given to the famous cutter Gabriel Tolkowsky to try out new cutting tools.
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Top 10 most famous diamonds The Orlov diamond The Orlov diamond is considered the largest diamond fund of the Moscow Kremlin. The origin of the stone, which has the shape and proportions of half a chicken egg, goes back to the 18th century in southern India. Although part of the Orlov's history has been lost, it is believed that he once served as the eye of a statue in an Indian temple.
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Top 10 most famous diamonds Sancy diamond The most famous owner of the Sancy diamond is King Henry III, who bought the stone from his attorney Nicolas de Sancy. The stone served as a beret decoration to cover the king's premature baldness.
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Top 10 Most Famous Diamonds The Kohinoor Diamond The Kohinoor or Mountain of Light diamond has a long history. The first mention of it appeared in 1304, when King Babur discovered the diamond, and since then it has passed to all the rulers of the Mughal Empire - a state in the modern territory of India and Pakistan.
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Top 10 Most Famous Diamonds The Hope Diamond Perhaps the world's most famous diamond is the Hope diamond. Nobody knows how big the stone was before it was cut, where it was found, and who gave it its original shape. It was first mentioned by the French merchant Jean-Baptiste and sold to King Louis XIV.
Explanatory note This project is short-term. After thinking through the technology and planning the work, responsibilities were distributed among the students. The guys worked with information sources: history, biology, chemistry, geology. We used material from the Yakutia magazine and information from the Internet system. The experiment was filmed with a camera. The results of the work were presented in the form of a presentation in the Power Point program. The multimedia project contains 18 slides with text, visual and video materials. This material can be used in chemistry lessons in the topic "Carbon" and in extracurricular activities.
Campaign of A. Makedonsky A well-known legend served as the basis for the work on the project. In the 4th c. BC. the troops of A.Macedonsky, making a trip to India, discovered in the mountains near Golconda the "Valley of Diamonds", at the bottom of which they saw placers of precious stones. Collecting diamonds was not possible due to the abundance of snakes infesting the valley. Therefore, the king suggested this way out: the servants threw pieces of fatty meat to the bottom of the gorge, to which diamonds stuck. The tamed eagles descended and brought meat with diamonds stuck to the feet of the emperor. Hypothesis: Is this legend based on real facts?
Project objectives To prove that A. Macedon with his army in the 4th century BC. e. tried to conquer India Determine the authenticity of the place of Golconda; To study the question of the origin of diamonds and their chemical structure; Consider the problem of the possibility of finding diamonds on the surface of the earth; Find out the facts of domestication and training of eagles; Prove that diamonds stick to fatty meat; Diamonds of Russia. Yakutia.
Pages of history In 331 BC. e. Alexander's campaign began in the depths of Persia. The army marched for four months. After fighting through the eastern regions of the Persian kingdom, Alexander's army invaded the Indus Valley. In a bloody battle, Alexander won a brilliant victory. Inspired by success, he announced a campaign in the Ganges valley and the Golconda valley. Further, the army, exhausted by heavy battles and transitions, refused to obey. Alexander had to turn back.
Hand eagles In the circus, trainers tame various animals. At home, people tame cats, dogs, and birds. But can people tame birds of prey? For the first time, people tamed hawks and falcons for hunting 2800 years ago, in the East. Its essence is that the game is not hunted by the hunter himself, but by a tamed feathered predator. The first book "On the Art of Hunting with Birds" was written in the 8th century. But its author is not a scientist, but ... Emperor of the Holy Roman Empire Frederick. Therefore, we do not exclude the possibility that A. Macedonsky was accompanied by tamed eagles in his campaigns. The Persian Shah, for example, kept 800 falcons for hunting, with a large number of mounted falconers, grooms and other servants.
The origin of diamonds Neither the diamond itself nor the places of its extraction (the legendary mines of Golconda) were known outside of India for a long time. Only after the Indian campaign of Alexander the Great, when the Macedonians plundered the treasuries of the Indian Maharajas, collected placers of precious stones right on the surface of the earth, the stone gained some fame in the world. It is assumed that diamond crystallizes as one of the first minerals during the cooling of the mantle silicate melt at a depth of 150-200 km at a pressure of 5000 MPa, and then is carried to the Earth's surface as a result of explosive processes accompanying the formation of kimberlite pipes, 15-20% of which contain diamond. There is another point of view, diamond crystallizes at a relatively shallow depth due to the partial oxidation of methane, at a temperature of over 1000 degrees and a pressure of 100-500 MPa. Small diamonds have been found in significant quantities in meteorites (urelites), as well as in giant meteorite craters, where remelted rocks contain significant amounts of fine-crystalline diamond or hexagonal high-barric modification.
Chemical substance - diamond Diamond is a natural compound of carbon, its allotropic modification. It is the hardest of natural substances. All 4 electrons of an atom form bonds. The crystal lattice is atomic. A cut diamond is a brilliant. It is used for drilling rigs, glass cutters, jewelry. Get artificial diamonds from graphite under high pressure.
Experiment Methodology of the experiment As a model of diamonds, pieces of glass were used, the density of which is close to the density of diamonds. Pieces of glass - “diamond models” were weighed, the mass was converted into carats. (0.2g = 1 carat)
"Koh-i-Nor" This is perhaps the only world-famous diamond that has never been sold for money. In the 18th century, this diamond was called the "Mountain of Light", not being the largest in the treasury of the British crown, it became one of the most mysterious diamonds of all time, thanks to its history shrouded in secrets. Now the gem is kept behind glass in the Tower of London. There is an Indian legend that says that a newborn was somehow found on the banks of the Yamuna River, a beautiful diamond was burning in his forehead, this was the legendary “Koh and Nor”. The elephant mahout's daughter picked up the child and brought him to the court. The baby turned out to be Karna, the son of the sun god. The net mass of the diamond was then 600 carats, it was erected on the statue of God Shiva, who brings enlightenment. The diamond is currently stored in London. It is inserted into the small Royal Crown of Great Britain.
Eureka "Eureka" is the first diamond to be accidentally discovered in South Africa in 1866. By the Orange River, near the town of Hopetown, lived a young man named Erasmus Jacobs. One day he discovered a small shiny stone among the pebbles. The stone had incredible beauty, and the young man decided to give it to his sister Louise. That's how an ordinary kid found the first diamond in South Africa, later called "Eureka." The governor sent the diamond to London for an exhibition. And the guy's family refused to take monetary compensation, deciding that an ordinary stone could not be worth that kind of money.
"Star of South Africa" In 1869, in the Hopetown area, a Negro shepherd found a diamond with a net weight of 83.5 carats. He brought the diamond to a farmer, Schalk Van Niekerk, who lived nearby. He, without hesitation, offered the shepherd 500 rams, 10 bulls and his horse in return, and he resold it for 11,200 pounds sterling. After the diamond was named the "Star of South Africa" and sold to the Countess of Dudley, whose name the diamond began to bear. In 1974, the gem was sold at Christie's for $552,000 and ended up in Geneva.
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Municipal educational institution
"Gymnasium No. 3 of Belgorod"
Diamond - legends and reality
Project work
Yablonovskaya Marina
Leader: geography teacher
Introduction……………………………………………………………………………….3
Chapter I. Diamond - the king of minerals……………………………………………………….4
1.1. Physical and chemical properties of diamond……………………………………….4
1.2. Conditions for the formation and presence of diamonds in nature……………………....6
Chapter II. Diamond is a natural resource……………………………………………………7
2.1. Extraction and enrichment……………………………………………………..............7
2.2. Application of diamonds………………………………………………………………..8
a) Jewelry processing………………………………………………………………..9
b) Production of synthetic diamonds……………………………………………..12
c) Industrial application……………………………………………………..13
Chapter III. Diamond complex of the world and Russia……………………14
3.1. Diamond complex of the world…………………………………………14
3.2. Diamond complex of Russia…..……………………………17
a) The history of discoveries of diamond deposits in Yakutia………………...17
b) Joint Stock Company "Diamonds of Russia"…………………………….………19
Chapter IV. Diamond is the property of human culture ……………………………20
4.1. Famous diamonds and diamonds………………………………………………..20
4.2. Treasures of the Diamond Fund of the Russian Federation….……………......................22
Conclusion…………………………………………………………………………...23
Bibliography………………………………………………………………………...24
Glossary of terms………………………………………………………………………25
Applications:
1. Map of world diamond mining………………………………………………..….27
2. Map of world diamond processing………………………………………………..27
3. Exhibits of the Diamond Fund of Russia…………………………………………..28
4. Presentation
INTRODUCTION
Diamond! This name is known to everyone. It is associated with ideas of incomparable brilliance and unsurpassed hardness. The name of the mineral is associated with the second property, which comes from the Arabic “al-mas” (hardest), or the Greek “adamas” (irresistible, indestructible).
He was considered the king of gems, the "stone of kings" and was valued above all treasures. Nothing can compare with it in hardness, and therefore it is truly eternal. And the high light refraction and wonderful play of colors in diamonds indicate that the gem arose in unusual conditions occurring in the depths of the Universe and the Earth. It seems that the well-known saying “the sky is in diamonds” has resurrected and reasserted itself.
American astronomer Marvin Ross from the University of California claims that the shiny surfaces of the planets Uranus and Neptune are not frozen water consisting of ammonia and methane, but a continuous layer of diamonds, in the helium-hydrogen atmosphere of which diamond snowflakes shimmering with all the colors of the rainbow whirl.
The first diamonds were found in India. According to ancient books, this happened over three thousand years BC, and the most ancient archaeological monument is a bronze Greek figurine with eyes made of Indian diamonds, now stored in the British Museum. It is believed to date back to 480 BC.
In 1983, during the construction of an irrigation canal in northern India near the city of Anantnaga, workers found a figurine of the god Rama, adorned with diamonds and gems, worth over a million rupees. Archaeologists have dated the find to the 14th century.
From time immemorial, a diamond has been given a special place among the representatives of the mineral kingdom. The exclusivity of the properties of the diamond gave rise to many legends, in which, along with the purest fiction, there were also descriptions of some of the real properties of the stone.
The main goal of this study is to compile a comprehensive description of one of the wonders of nature - the diamond mineral, as well as a story about its presence in nature and human use. The following tasks follow from the goal:
1. Get acquainted with the main physical and chemical properties of diamond.
2. Find out the conditions for the formation of the mineral and its distribution in the lithosphere.
3. Describe the history of diamond mining in the world and in Russia.
4. Give a brief description of the world and Russian centers of diamond mining and processing.
5. Tell about famous rough and polished diamonds, including those in the Diamond Fund of the Russian Federation.
The long-standing topic is of great interest because we all would like to at least once plunge into the “big problems” that concern not us personally, but Russia as a whole. The diamond industry is a matter of national importance, from which, with a reasonably built economy, there could be a guaranteed and stable income to the state treasury.
The completed work can be in demand by students interested in geology and mineralogy, history and economics of the countries of the world, as well as teachers of history, geography, and chemistry. The information provided will complement the content of the lessons, help in the preparation of reports on subjects, extracurricular activities.
CHAPTER I. DIAMOND - THE KING OF MINERALS
DIAMOND - a mineral, a crystalline cubic polymorphic modification of native carbon, surpassing all minerals in brilliance, beauty and hardness.
Natural diamonds in their "raw" form are rather nondescript. In most cases, they are rather small (1-5 mm in diameter) grains with a dull matte or rough surface, often covered with films, crusts and impurities of foreign substances. And even well-formed transparent diamond crystals with smooth facet surfaces do not have the brilliance and "play" so typical of gemstones, and therefore usually do not attract the attention of non-specialists.
1.1. Physical and chemical properties of diamond
Chemical composition
Diamond consists of pure native carbon, but usually contains small impurities of various chemical elements that are part of the crystal structure or inclusions of other minerals. Colorless varieties are pure carbon, colorless transparent varieties are characterized by a structural admixture of nitrogen (0.3%), although “nitrogen-free” diamonds are also found. Colored and opaque diamonds contain impurities of silicon dioxide (SiO2), magnesium oxide (MgO), calcium oxide (CaO), iron oxide (FeO), iron oxide (Fe2O3), aluminum oxide (Al2O3), titanium oxide (TiO2); Graphite and other minerals occur as inclusions. The content of impurities reaches 5%.
Color
In its pure form, it is colorless, water-transparent, with a strong play of colors. The color of diamonds varies widely and is of great importance when evaluating jewelry and sometimes technical stones. The most common diamonds are colorless, brown, gray, yellow, blue and black, as well as colored in various shades of yellow, brown. Less common are varieties with greenish, bluish and pinkish hues. Stones of pure bright tones of blue, green and red are quite rare.
The best quality diamond is colorless, with a strong brilliance and a beautiful play of color, such a stone is said to be “pure water”. However, for the most part, diamonds come with an "overcolor", that is, with a faint shade of other colors: wine yellow, straw, brown, dirty green, bluish, reddish and black. Among them, transparent diamonds painted in red, blue, yellow, pink and black are highly valued.
The color of many crystals is not evenly distributed, but concentrated in separate areas. When heated, some brown diamonds take on a golden hue, while pale pink diamonds turn deep pink. True, after a short time the original color is restored.
The surface of the stones of the most ancient (more than 1-1.5 billion years) deposits has a green color, which disappears when the crystal is mechanically processed. The appearance of a green “shirt” on diamonds is associated with prolonged exposure to radioactive irradiation. The formation of a dark green shell on the colorless core of a diamond crystal under the influence of radiation was also observed in laboratory conditions.
Morphology
Diamond crystallizes in the cubic system (syngony).
Crystal structure
Face-centered cube lattice; each atom is surrounded by four others arranged in a tetrahedron. Carbon atoms are located in it at the nodes of two cubic lattices with centered faces, very tightly inserted one into the other (a = 3.5595 A).
Diamond crystals are giant polymeric molecules and are usually shaped like octahedrons, rhombododecahedrons, less often cubes or tetrahedra. Twins and intergrowths of several crystals are frequent, convex faces and curvilinear ribs are characteristic. The faces of the crystals are usually covered with growth or dissolution figures in the form of protrusions or depressions of various shapes, shading, curvature of the faces; irregular, distorted crystals are observed. There are also radially radiant, fibrous, shelly or fine-grained aggregates (ballas, board, carbonado).
The shapes listed are limited to flat or flat-stepped faces.
Along with flat-faced crystals, all deposits contain, and sometimes predominate, crystals with convex curved faces - curved ones.
The surface of both flat and curved diamonds is rarely smooth and shiny. Almost always, it is covered with numerous bumps, depressions, shading, annular and stepped protrusions, which scatter light, causing the dull, greasy or glassy luster of most natural diamonds in their natural form.
Crystal sizes
They range from microscopic to very large. The mass of the largest Cullinan diamond, found in 1905 in South Africa, was 3106 carats (0.621 kg). The weight of diamonds is measured in carats, a fractional unit of mass used in jewelry. Referred to as "carat". A metric carat is equal to 200 mg - 2 10-4 kg. Large transparent diamond crystals are first class gems.
Hardness
Diamond is the hardest of all natural substances. On the Mohs scale, the relative hardness of diamond is 10, the absolute hardness is 1000 times higher than the hardness of quartz and 150 times that of corundum. Maximum hardness on the faces of the octahedron, minimum on the faces of the cube; cutting, sawing and polishing of diamonds are based on this. The hardest of natural gemstones; polished only with diamond powder.
Shine . Strong, diamond to bold.
Transparency. Transparent, cloudy.
Damn. Does not have: scratches the proof plate
Break. conchoidal.
Cleavage. Perfect on an octahedron (111), which causes brittleness and somewhat limits the use of diamond.
behavior in acids. Insoluble.
similar minerals. None.
Associated minerals. Olivine, chrome spinels, pyrope, magnetite, ilmenite, hematite, graphite, calcite.
Density. High (3.511 g / cc).
refractive index. High (from 2.417 to 2.421).
Dispersion. High (0.0574). They cause bright brilliance and multi-colored "play" of faceted gem diamonds.
Good semiconductor.
Radiation in x-ray, cathode and ultraviolet rays. Most diamonds begin to glow (luminesce) in blue, green, pink and other colors.
Interaction with fat mixtures. It adheres to certain fat mixtures, which is the basis for the most widely used fat method for extracting diamonds in processing plants.
admixture of nitrogen. The properties of diamond change dramatically depending on the presence (type I) or absence (type II) of nitrogen impurities. Type I is characterized by anomalous birefringence, low photoconductivity, no electrical conductivity, absorption in the infrared (between 8-10 microns) and ultraviolet (from 3300 A) ranges, high thermal conductivity. Nitrogen-free diamonds (type II) are practically isotropic, with high photoconductivity, do not absorb infrared radiation and are transparent in ultraviolet radiation (up to 2200 A), and have extremely high thermal conductivity.
Behavior on heating. In air, powdered diamond burns on a platinum wire at 850°C to form carbon dioxide (CO2); in vacuum at temperatures above 1500 ° C, it transforms into graphite.
From a chemist's point of view, pure coal, graphite and diamond are one and the same. The only difference is that the carbon atoms are stacked differently in them. The fact that diamond is pure carbon and nothing else has been known for a hundred and fifty years. But people have learned to “fold” carbon atoms into diamond crystals only quite recently.
Graphite crystal lattice
Diamond crystal lattice
The properties of both modifications of carbon (diamond and graphite) are presented in Table 1.
Table 1
Properties | Diamond | Graphite |
Colorless | Grey-black |
|
Hardness | The hardest substance (H=10) | Very soft (H-1) |
crystals | Grainy | Scaly |
Syngony | cubic | Hexagonal |
Crystal cell | cubic | Hexagonal layered |
Density, g/cm3 | ||
Electrical conductivity | Missing | Conductor |
Behavior on heating | At 1500 ° C it transforms into graphite | At temperatures above 2800 ° C, sublimation occurs |
1.2. Conditions for the formation and presence of diamonds in nature
It is assumed that diamond crystallizes as one of the first minerals during the cooling of the mantle silicate melt at a depth of 150-200 km at a pressure of 5000 MPa, and then is carried to the Earth's surface as a result of explosive processes accompanying the formation of kimberlite pipes, 15-20% of which contain diamond. There is another point of view, according to which diamond crystallizes at a relatively shallow depth due to the dissociation or partial oxidation of methane in the C-H-O-S gas system at a temperature above 1000 ° C and a pressure of 100-500 MPa.
Diamonds are also found in deep-seated eclogites and some deeply metamorphosed garnet gneisses. Small diamonds have been found in significant quantities in meteorites (ureilites), as well as in giant meteorite craters, where remelted rocks contain significant amounts of fine-grained diamond or hexagonal high-pressure modification (lonsdaleite).
Diamonds were born deep underground, when red-hot magma broke through the earth's crust, forming peculiar pipes in it, similar to the vents of volcanoes. These vents are filled with bluish clay. By the name of Kimberley - the places in South Africa where it was first discovered, the bluish clay was called kimberlite. Kimberlites are composed mainly of olivine, pyrope, ilmenite and other minerals. It is here that precious crystals are hidden, formed during the solidification of molten magma in the thickness of carbon-rich rocks. Diamonds from kimberlites and meteorites differ from diamonds found in meteorite craters and metamorphic rocks by an increased content of the heavy carbon isotope.
As a result of explosive processes, kimberlite is carried to the surface and forms the so-called. "explosion tubes". Such pipes form primary diamond deposits.
In addition, diamonds are mined from much more widespread and usually richer alluvial deposits, represented by sea and river sands and pebbles, in which diamonds accumulate due to the mechanical destruction of the primary host rocks.
CHAPTER II. DIAMOND IS A NATURAL RESOURCE
2.1 Mining and enrichment
Diamonds are not ubiquitous, and therefore it is very important to choose the right areas where it is planned to search for new deposits. It has long been known that diamond deposits are located in areas characterized by a calm, almost horizontal occurrence of rock layers, and are not found in those areas where the earth layers are crumpled and collected in steep folds. Regions of the first type are called platforms in geological terminology, and regions of the second type are called folded or geosynclinal regions.
To detect diamond deposits in a predetermined area of the platform area, various methods are used, which are usually used not one by one, but several at once. A set of complementary prospecting methods is selected taking into account the peculiarities of the geological structure of the area and the results of geological exploration work previously carried out on its territory.
The arsenal of methods developed to date for detecting diamond deposits is quite diverse, but they all fall into three main groups. The first group includes search methods that can be characterized as proper geological, the second - geophysical, the third - geochemical. The most effective and widely used are geological and geophysical methods.
Among the geological methods of prospecting for diamond deposits, the leading role belongs to schlich and small-volume sampling, which are subjected to river sediments, as well as loose masses of weathered rocks that make up the slopes of river valleys and mountains.
The first primitive diamond mining was carried out in India long before the beginning of our era. For many centuries this country remained the only supplier of sparkling stone to the world market. And only at the beginning of the XVIII century it became known about the discovery of diamond deposits in Brazil. New deposits turned out to be much larger and richer, as a result of which Brazil was ahead of India in diamond production. Brazil maintained this championship for about 150 years, until the second half of the 19th century, when the richest deposits of South Africa were discovered.
For a long time, diamonds were mined by disenfranchised slaves, whose lot was excessive manual labor under the scorching rays of the sun and in the damp darkness of underground workings under the vigilant supervision and scourges of ferocious overseers. As a result of collapses of the walls and roofs of mine workings, diseases, malnutrition and other reasons, thousands and thousands of miners of the precious stone died.
At the end of the XIX century. primary diamond deposits were discovered, the exploitation of which was fraught with even greater difficulties and dangers than in the development of placers. The most dangerous was the development of diamond pipes on the branch system. Hundreds and thousands of greedy seekers of profit rapaciously developed their withdrawals, disregarding the interests and safety of neighbors. In the process of excavation of kimberlite, an explosion occurred at the place of the pipe and every year deepened an extensive pit. Only diamond rock was extracted, and the walls of sandstones and shales containing kimberlites rose higher and higher above the bottom of the pit.
In the course of ongoing work, collapses occurred more and more often, which did not always do without human casualties. As a result, open mining was stopped, and further exploitation was carried out underground. However, this method required the sinking of deep mines and complex equipment, which was neither possible for single prospectors, nor for prospecting artels, who did not have sufficient capital and knowledge. They were replaced by large capitalist companies.
The development of primary deposits by the underground method is usually carried out as follows. At a distance of 300-400 m from the pipe, a shaft passes. The shaft of the mine is connected to the pipe by a horizontal tunnel - the main adit. The excavation of kimberlite is carried out by chambers with a height of 10-12 meters or more. One main and several short auxiliary adits associated with it allow you to choose a block up to 200 m. After that, the shaft is deepened and the whole cycle of work is repeated.
For a long time, diamond-bearing pipes were known only in South Africa - here kimberlite came out directly to the surface. And in all other places - in Brazil, Indonesia, Australia, here in the Urals - diamonds were found only along the banks of rivers, in stone placers. The water carried the diamonds away from where they once were and scattered them along the riverbeds. Only almost a hundred years after the discovery of diamonds in South Africa, it was possible to find new diamond pipes - in a region that least of all resembles the South African steppes - in Yakutia. Diamond-bearing clay is mined here in an open way - excavators and bulldozers. Alluvial diamond deposits in riverbeds can be mined using dredges, just like gold placers.
In Yakutia, the upper horizons of diamond-bearing kimberlite pipes are mined in an open pit. It provides a high level of safety and labor protection for all employees. All work is fully mechanized.
The kimberlite, loosened by explosions, is captured by excavator buckets and loaded into trucks that deliver diamond ore to processing plants.
At processing plants, kimberlite is first ground in special mills, with special care being taken not to damage the largest diamond crystals. The crushed material enters the washing machines, each of which is a stirrer and a centrifuge, and ensures that light particles are washed away. The remaining material is divided into several classes according to grain size and then sent to jigging machines, where it is further enriched. The volume of the concentrate obtained as a result of all these operations is many times less than the volume of the original kimberlite.
To extract diamonds from clay rock, it is passed through crushers with elastic bearings - their rolls grind clay, but cannot damage hard diamond. The crushed clay is washed with water: the pieces in which the diamonds are hidden, being heavier, sink to the bottom. In order to separate the diamonds from the remaining ground clay, it is dried and then passed through vibrating tables smeared with petroleum jelly. Waste rock rolls, diamonds stick.
2.2. Application of diamonds
Diamonds have been known since ancient times. Already thousands of years ago, they attracted the attention of people with their beauty. The crowns and scepters of kings were adorned with sparkling diamonds - faceted diamonds. But from the end of the 19th century Diamonds began to be valued not only for their beauty, but also for their hardness.
The time has come for a scientific and technological revolution. The diamond drill was invented - and it turned out that it drills hard stone much faster than any other drill. Grinding wheels with diamond grit appeared - and it turned out that they grind stubborn metals better than any other grinding wheels. Diamond cutters were created - an unsurpassed tool for processing superhard alloys. From a precious trinket, the diamond has become the most important and, moreover, irreplaceable material for industry. For technical needs, industrial diamonds began to be widely used, which are unsuitable for jewelry - small, not very clean, etc.
a) Jewelry processing
Diamonds have long been used as the most exquisite jewelry and have been of great monetary value. Transparent colorless or beautifully colored diamond crystals suitable for cutting (crystals of jewelry varieties) are precious stones of the 1st class, as well as sapphire, ruby, emerald, alexandrite. Jewelers divide diamonds into 1000 varieties depending on transparency, tone, density and uniformity of color, the presence of cracks, mineral inclusions and some other features.
Gem diamonds typically account for 20-25% of mined diamonds; in placer deposits, their share is noticeably higher than in primary deposits. Jewelry diamonds are transparent, without cracks and inclusions. When they are cut, the greatest brilliance and play of the stone are revealed, natural defects are eliminated, and about 50% of the original mass is lost.
GEMS, minerals with special properties used for jewelry purposes. Colorless or a beautiful pure color tone, most gemstones are distinguished by their brilliance, transparency, strong light scattering, high hardness, and the ability to take a cut.
Precious stones are conventionally divided into 5 classes:
First class - diamond, ruby, sapphire, emerald;
The second class is alexandrite, orange, green and violet sapphire, noble black opal, noble jadeite;
Third class - demantoid, spinel, noble white and fire opal, aquamarine, topaz, rhodonite, tourmaline;
The fourth class is chrysolite, zircon, kunzite, moonstone, sunstone, yellow, green and pink beryl, pyrope, almandine, turquoise, amethyst, chrysoprase, citrine.
Diamond not only refracts and reflects light rays very strongly, but also has another very important optical property that determines the exceptional beauty of this stone. It consists in a large difference in the refractive indices of diamond for rays of different colors.
High light refraction and dispersion create a unique "game" of diamonds, expressed in an enchanting combination of the brilliance of the upper facets with bright light flashes and continuous overflows of all the colors of the rainbow from the inside of the stone during its slow rotation.
DIAMOND
(from the French brillant, lit. - brilliant), a flawless gem diamond, the special artificial cut of which brings out its brilliance to the maximum. Due to the high dispersion in reflected light, the diamond "plays" with all the colors of the rainbow. The mass of a diamond is measured in carats (0.2 g).
Diamond cut elements: 1 – crown; 2 - pavilion; 3 - kyulass; 4 - girdle; 5 - platform
The real beauty, brilliance and enchanting "play" of light rays in diamonds is revealed and achieved as a result of special mechanical processing of natural transparent crystals, which are then called diamonds. Large diamonds are called solitaires. Processing consists in splitting (chopping) or sawing, subsequent turning and faceting of crystals from all sides to give them a special shape.
For jewelry processing of diamonds, specialists use special stone-cutting and grinding tools.
Cracking diamonds allows, with insignificant losses of raw materials and low labor costs, to divide the crystals into parts for their more efficient use, in particular, to get rid of crystal areas with defects and foreign inclusions. This operation requires great skill, since even with one careless blow, the diamond can be turned into fragments unsuitable for making diamonds.
sawing diamonds necessary for separating natural crystals into parts when processing them into diamonds. It has been in use since the 17th century. In those days, iron wire, cariculated with diamond powder, was used to cut diamonds. The process of sawing large crystals lasted for many months, and at the same time a large amount of diamond chips was consumed. Sawing diamond "Regent", weighing 410 carats, lasted about two years. Later, diamond saws appeared, which did not differ significantly from modern ones.
Diamond turning is one of the most important operations in the technological cycle of manufacturing diamonds. The degree of use of raw materials and the quality of finished stones largely depend on it. The purpose of turning is to give the workpiece the shape of a future diamond, prepare it for cutting and remove all or at least some of the defects. The shape of the future diamond largely depends on the original shape of the diamond.
Cut - mechanical processing (cutting and polishing) of natural and synthetic precious and semi-precious stones for jewelry and technical purposes.
Cutting gives an aesthetic shape, reveals the natural beauty of the stone and features specific to each mineral: color, brilliance, transparency, light dispersion (the ability of a mineral to decompose white light into different colors), pleochroism, iridescence, opalescence, etc.
Gemstone raw materials usually have a nondescript look: when the world's largest Cullinan diamond was presented to the English king Edward VII, the king was disappointed with its resemblance "to ordinary glass" and said that on the street he "would have thrown it aside like a simple cobblestone." The processing technology is determined by the natural shape, size of crystals, their transparency, color distribution, optical properties, etc. Usually, they strive to preserve the mass of the stone as much as possible, take into account the uneven distribution of color, the presence of inclusions, cracks and other defects.
Precious and semi-precious stones are cut - diamond, emerald, ruby, sapphire, spinel, aquamarine, topaz, tourmaline, etc., which have high hardness, transparency, beautiful color and dispersion; translucent and opaque minerals with a beautiful color, pattern and sufficient hardness - agate, carnelian, jasper, turquoise, malachite, etc., as well as gems with a play of colors in reflected light (opalescence, iridescence) - opal, moonstone, mother of pearl, etc. Gem raw materials are first sawn or pricked to obtain blanks that are faceted and then polished.
Diamond cutting is a complex and very laborious process. The processing of large stones takes months, and unique ones take several years. The resulting diamonds are about 1/2, and sometimes only 1/3 of the original mass of raw diamond. The final cost of the stone doubles or triples. Before cutting large diamonds, special calculations are carried out in order to establish such a shape of the future diamond that will provide the best game and allow the mass of the original crystal to be preserved as much as possible. As a result, diamonds are not always isometric and may have an elongated and even teardrop shape.
Main types of cutting
The combination of facets of various shapes and sizes applied to the surface of the gem makes it possible to distinguish the main types of cuts. The most ancient is spheroidal smooth polishing of the stone surface, giving it a lenticular, convex-concave or convex-flat (cabochon) shape and making it possible to better reveal the color or iridescence. Cabochon shapes are used for processing opals, carnelian, moon and sun stones, turquoise, malachite, etc. With step (ladder) cutting, a different number of steps with horizontally located ribs are applied on the front and back sides of the stone. There are many varieties of step cut. The most common are the wedge-shaped, when each pair of stepped faces turns into 4 wedge-shaped faces, and the octagonal "emerald" cut, in which the color of the stone is best shown.
For diamonds and other minerals with a strong dispersion of light, a brilliant cut is predominantly used, in which the stone is covered with numerous flat surfaces - facets. With a full brilliant cut, on the front (top) side (crown), on which the platform (tablet) is located, three belts of facets are applied in such a way that 33 facets are located on the front side, together with the platform. On the back side (pavilion) there are 24 facets; thus, a full brilliant cut consists of 57 facets. The resulting diamond has a round shape in plan, its diameter is called a girdle. The maximum brilliance of a rounded diamond is achieved by observing the precisely calculated proportions of the pavilion faces, which ensure full internal reflection of light. The incoming beam of light should be fully reflected twice from the back facets on opposite sides of the stone and exit the crown, creating maximum brilliance.
Diamonds differ in the general shape of the stone, the nature of the cut. According to the nature of the cut of diamonds, there are three main types: the actual diamond, step and rose cut. In diamond-cut stones, the faces of different tiers (belts) are staggered relative to each other. The outlines of the faces correspond to a rhombus or a triangle. The platform at the upper end of the stone has the shape of a regular polygon. This type of cut is mainly used on round and fancy diamonds. The step cut differs from the brilliant cut in that the faces of adjacent tiers are located one above the other, and their outlines correspond to trapezoids or isosceles triangles. The platform on the upper surface of the stone has the shape of a polygon with sharp or cut corners. This type of cut is typical for rectangular diamonds.
Small and sometimes large diamonds are often cut in the form of a "rose" or "rosette". With this type of cut, the stone has a flat base, and its upper part is convex and consists of 6, 8, 12, 24 or 32 faces converging at one vertex. In shape, these diamonds are somewhat reminiscent of a bouquet of roses, which explains the name of this type of cut. Stones with 12 or fewer facets are called "Danver roses" and those with more facets are called "crowned roses". Sometimes a double rose cut is used, in which the upper and lower parts of the stone are limited by a rose. Rosettes have a much weaker play of light than brilliant-cut stones, and therefore, with the same size, color and clarity, rose-cut diamonds usually make up about 20% of the value of brilliant-cut diamonds.
The rose cut appeared in the middle of the 17th century. At the end of the same century, brilliant cutting began to be used. The latter was continuously improved up to development in the first half of the 20th century. "ideal" cut.
Brilliant cut makes the most of the optical properties of the diamond, provides the maximum play of light and brilliance of it, thanks to which the natural beauty of the mineral is best revealed.
While maintaining the mass of the stone, it is often cut too "shallow" or too "deep"; it is not easy to spot these cutting defects. The following proportions of a brilliant cut are considered ideal (in % of the diameter of the girdle): the height of the upper part is 14.4; lower part - 43.3; overall height - 57.7; platform diameter - 56.0. Small diamonds, having only one row (or belt) of facets, have 8 facets on the front and back sides and are called octahedrons. A star or double cut has two bands of facets. There are also fancy cut types, for example, the American brilliant cut - 80 facets in four rows (cut in the 20th century).
The shape of the stones can be oval, pear-shaped, heart-shaped, drop-shaped (for pendants) - briolette, pandelok; elliptical - marquise or shuttle, "olive" or "olive". A profile cut has also been developed that uses the principle of automobile light reflectors, when diamonds are cut into plates 1.5 mm thick, the upper side is represented by a smooth polished plane, and the lower side is covered with reflective grooves with an interval of 0.9 mm between them. With modern cutting, from 20 to 50% of the mass of the raw material is ground off.
History reference
Gemstones have been cut into cabochons since ancient times. The first major generalization of "On the Polishing of Precious Stones", made in Europe by Theophilus, dates back to 1100. Even in ancient India, it was noticed that when one diamond is rubbed against another facet, they are polished and the brilliance increases. Some time later, in India, and later in Italy, France and Belgium, diamonds began to be cut with a “platform” or “octahedron”. For such a simple cut, natural octahedral (octahedral) crystals were taken or blocks of the corresponding shape were cut out from diamond crystals of a different shape. The faceting consisted in grinding the opposite vertices of the octahedron until only one of them formed a new wide flat face, called the "platform", and in place of the second, a small blunting face, known as the "culet".
In the XII-XIII centuries. grinding mills appear in Europe. In 1456, in Bruges, diamond powder was first used for cutting diamonds. Brilliant cutting appeared in Paris around 1600; Until that time, diamond powder had only been used to polish the natural facets of diamond crystals or to cover it with numerous randomly arranged small facets. On this basis, the ancient Indian masters developed the rose cut (faceted hemisphere); ideally, this type of cut has 24 triangular facets and a flat base (the famous Orlov diamond has a similar shape).
It is believed that Ludwig Berkem was the first European to learn how to cut diamonds. He noticed that when one diamond is rubbed against another, they are polished. In 1454, he cut his first diamond, which later received the name "Sancy". After Berkem's death, the secret of polishing diamonds was lost, but soon found again.
Grinding consists in giving the surface of the workpiece regularly arranged faces of a certain shape, polishing provides a mirror-smooth surface on the faces obtained during grinding. Cutting is considered to be the most complex and responsible process in the manufacture of diamonds. For its successful implementation, in addition to knowledge and experience, artistic taste is also required.
In the future, people tried to process diamonds in such a way that the largest possible number of light rays falling on its facets would undergo surface and internal reflection. To do this, the stones had to be given the shape of a polyhedron with a certain mutual orientation of the faces.
in Russia until the 18th century. cabochons predominated. The development of the art of cutting is associated with the creation in 1724 of the Peterhof (by decree of Peter I) and in 1774 of the Yekaterinburg cutting factories. Cutting is the final process of processing diamonds in order to give them an aesthetic shape, to achieve the brilliance characteristic of this mineral.
b) Production of synthetic diamonds
The need for cheap artificial diamonds led to the creation of the first artificial diamonds, first in Sweden in 1953. In the United States of America, the General Electric Company received synthetic diamonds in 1956. In the same years, similar success was achieved in the USSR. In 1971, General Electric managed to grow an artificial diamond weighing one carat.
To synthesize diamond, it was necessary to recreate the conditions under which diamonds were formed in the bowels of the Earth. And for this it was necessary to heat carbon to several thousand degrees and compress it under pressure of several hundred thousand atmospheres. Scientists in our country and abroad have managed to design special devices in which such conditions can be created.
The technology for the production of artificial diamonds is quite complex. Synthesize diamonds at a temperature of ° C and a pressure of MPa (50-60 thousand atmospheres) from graphite powder mixed with powdered iron, nickel, chromium. Diamonds crystallize due to the fact that the melt at high pressures is not saturated with respect to graphite and supersaturated with respect to diamonds. In the late 1990s, the synthesis of film diamonds for the electronic industry from methane (CH4) was mastered by blowing a hydrogen-methane mixture heated to 1000°C. Using different synthesis modes, you can get diamonds of different colors: yellow, blue, red, brown.
The largest artificial diamond - weighing just over 30 carats - was obtained by De Beers. However, this stone is not of gem quality. About 40 tons of fine-grained diamonds are synthesized annually in the world and are used to produce abrasive powders. Artificially obtained jewelry diamonds are much more expensive than natural ones, but in terms of their hardness they are in no way inferior to natural ones.
Since the 1960s, artificially synthesized gemstones have become more and more widespread. Artificial diamonds, rubies, sapphires, emeralds, alexandrites, amethysts, rock crystal, opal are grown in laboratories. Using the method of chemical synthesis to obtain abrasive powders, up to 40 tons of cheap fine-grained diamonds are produced annually.
In addition, materials are grown that do not exist in nature, but which, when cut, look like precious stones. Among them is an imitation of a diamond - cubic zirconia, first obtained in Russia in 1972.
zirconia, a group of synthetic single crystals based on zirconium or hafnium oxides. Known as imitation diamond. For the first time (in 1972) they were created at the Physical Institute of the Academy of Sciences of the USSR (abbreviated as FIAN, hence the name).
There are two centers for the production of artificial diamonds in Russia - Moscow and Novosibirsk. The secrets of diamond synthesis are held in Ukraine and Belarus. The largest foreign manufacturers - the firms "General Electric", "De Beers", "Sumimoto Electric" - in principle sell their products only for use in technical purposes.
imitation diamond
Colorless zircon, synthetic rutile, strontium titanate, synthetic colorless spinel and corundum, diamond doublets and lead glass are used to simulate diamonds; as well as emerging synthetic yttrium aluminum garnet (YAG), gadolinium gallium garnet (GGG), and cubic zirconia. All these compounds are softer than diamond, do not have the characteristic blue luminescence, and differ in refractive index.
c) Industrial application
From the end of the 19th century diamonds are beginning to be used in production. At present, the economic potential of the most developed countries is associated with their use of diamonds.
Thanks to scientific and technological progress in the second half of the 20th century, it became possible to change the color of natural diamonds. By bombarding diamond crystals with electrons, protons, neutrons, followed by processing, it is possible to color them in yellow, blue, green, brown colors, and elementary particles placed in the accelerator become blue or blue. Depending on the nature and intensity of irradiation, the color change can occur only in the surface layer or throughout the entire volume of the crystal, it can disappear after a short time, or it can remain unchanged for years.
What properties of diamond determine its widespread use in various areas of the economy? First of all, of course, exceptional hardness, which, judging by the wear rate, is 150 times higher than that of corundum, and tens of times higher than that of the best alloys used to make cutters.
Technical diamonds are applied:
When deep drilling of rocks (reinforcement of drill bits),
When machining a wide variety of materials,
For the manufacture of grinding and cutting tools, grinding material,
Since 1869, South Africa has been mining diamonds from river placers, and then from primary deposits represented by kimberlite pipes. The average content of diamonds in kimberlites is about 0.5 ct per 1 m3 of rock, in placers it is 0.25-0.5 ct per 1 cubic meter. m. The names of deposits are usually associated with the names of large kimberlite pipes with a diameter of more than 0.5 km. These include the already exhausted mines of South Africa: Jagersfontein, Kimberley, De Beers; large operating mines are located at the Premier, Finsch, Koffifontein and other pipes; in Tanzania, a huge Mwadui pipe with a diameter of about 1.5 km is known; pipes over 1 km in diameter are known in Botswana; the large Mote pipe is located in Lesotho.
The African continent turned out to be extremely rich in primary and alluvial (including offshore) diamond deposits, which are exported from South Africa, Zaire, Botswana, Angola, Namibia, Ghana, and Sierra Leone.
Currently, the annual world diamond production is estimated at 100 million carats (20 tons), of which 40 million are in Africa and 30 million each in Russia and Australia (Appendix 1).
The mass of mined diamonds is usually 0.1-1.0 carats, large jewelry stones (over 100 carats) are rare. The price of gem-quality rough diamonds is about $100 per carat. The cost of diamonds varies greatly depending on the purity of the “water”, the shades of the color of the “colors”, the presence of inclusions and defects, the size of the stones, the quality of the cut, etc. The usual price of a carat of diamonds is from 400 to 1000 dollars.
USA (New York) - processing of large diamonds;
India (Surat) - cutting the cheapest yellow diamonds;
Israel (Ramat Gan) - an economical cut that preserves the mass of the stone as much as possible, often to the detriment of the quality of the cut.
Among foreign jewelry firms, the most famous are TIFFANY * (Tiffany and Co), an American jewelry firm, distinguished by a stable high class and purity of style of its products, and W. A. Bolin, a Swedish jewelry firm, one of the largest in Scandinavia.
* "Tiffany" (Tiffany and Co) originates from a small trinket shop on the outskirts of New York (1837). The company's founder Charles Lewis Tiffany () turned to the jewelry trade in 1841. Since 1851, the company has been constantly working on developing new types and expanding the range of products, improving production technology.
A significant contribution to the formation of the prestige of the company was made by an excellent applied artist, the son of the founder of the company - Louis Comfort Tiffany (). His most famous works are things made of iridescent glass and jewelry, which is a fantastic combination of glass, enamels, colored stones, and various metals. In subsequent years, the company attracted the leading couturiers of the world - Jacques Schlumberger (1907-87), Eliza Peretti (1940), Paloma Picasso (1949) and others.
The company is constantly working with both high-quality products for middle-class buyers, and with the rarest pieces of jewelry. At various times, the French Crown Jewels and unique gems, including the Tiffany diamond (128 carats), passed through the firm. The eminent scientist George Frederick Kunz worked for a long time on the formation of the gemological (see gemology - glossary of terms) collection of the company. Modern designers of the company, along with high-level jewelry, create exclusive collections of artistic silver, crystal, porcelain, silk and glass products.
Among the clients of the firm at various times were prominent figures in literature and art, businessmen, well-known political figures, including Mark Twain, Sarah Bernhardt, Abraham Lincoln, John F. Kennedy.
** BOLIN (W. A. Bolin), a Swedish jewelry company, one of the largest in Scandinavia.
It originated in Russia in 1796 on the basis of the diamond workshop of the master A. Rempler in St. Petersburg, and was a court supplier. Since 1852 it had a branch in Moscow. The Petersburg branch was famous for making jewelry with large stones, in the Moscow branch they made souvenirs from gold and silver and numerous silver items (in the classical style, in the styles of historicism and modernity), table setting items. The company existed in Russia until 1916, after which it settled in the homeland of the ancestors of the Bolin family - in Sweden.
Works with platinum, gold, silver and precious stones. Its leading designers include Barbu Littmark and Juliana Pfeiffer, who have created a range of original enamel pieces. Jewelry and artistic silver of the company are stored in the most significant public and private collections in Russia, Sweden, USA, England, Germany, Denmark and other countries (in Russia in the Armory, the Historical Museum, the Hermitage), as well as in the collections of the royal houses of Denmark and Sweden.
Diamond complex of Russia
The first diamond was found in our country in the Urals in the 19th century. In 1954, as a result of exploration work on the Siberian platform, in the basin of the Bolshaya and Malaya Botuoboi rivers, diamonds from Yakutia were discovered.
At present, the main industrial diamond deposits in Russia are concentrated in three large geographically separated diamond-bearing regions:
Republic of Sakha (Yakutia) - 82.4% of reserves and 99.7% of production;
Perm region - 0.15 reserves and 0.3% of production.
In Russia, high-quality cutting of small stones is carried out at enterprises in Moscow, St. Petersburg (“Russian Gems”), Yekaterinburg and Smolensk.
a) History of discoveries of diamond deposits in Yakutia
Yakutia... This mysterious and hard-to-reach land has always attracted brave, inquisitive and enterprising people, among them our wonderful contemporaries - the discoverers of diamond deposits, people of a truly legendary fate and high civic duty. Their path to a deep and serious knowledge of this amazing land lay through science, selfless work, and overcoming all obstacles.
A milestone on the path of Soviet people to the treasures of the northern bowels was the theoretical justification in the late 1940s by an academician of the possibility of finding diamonds in the Lower Tunguska and Vilyui basins. The first diamond in the territory of Yakutia was found in Vilyui in August 1949 by the geological party of the Tunguska expedition led by. This made it possible to draw an important conclusion that the primary sources of diamonds that feed the Vilyui placers below the mouth of the Malaya Boutobiya are located somewhere in its basin. On August 7, 1949, the Vilyui spit Sokolinaya flared up with a spark of hope. The bluish light of the first Yakut diamonds warmed the geologists, highlighting the routes of new discoveries on the Siberian platform. Arguments, which were so lacking for organizing a territorial geological service to move to the territory of Yakutia and expand the front of prospecting, were now presented in kind and, like a magic key, opened the doors to the highest state authorities.
The offensive of the subsoil explorers was gaining momentum, the best forces of geologists and science were thrown into the search for diamonds. One after another, invisible diamond fortresses, armored with permafrost, surrendered. Behind the placers, primary deposits were found - kimberlite pipes "Zarnitsa", "Udachnaya", "Mir" - stitches of pyropes accompanying diamonds led to them. The keys to the treasures were found thanks to the original pyrope search technique developed in the Soviet Union. Thus, the first half was won in the cruel diamond game imposed on our country by the strategists of Western monopolies (the theory “diamond is a child of the tropics”).
Now it was necessary to win the second half, to win completely - to begin the industrial development of diamond deposits. After the discovery of the first diamonds in Vilyui, a project was drawn up for prospecting for diamond deposits in Yakutia for 1960-1965 under the leadership of the participation.
On August 21, 1954, successfully applying the Pyrope Survey Method developed in Leningrad, the geologist discovered the first primary diamond deposit in our country, a kimberlite pipe, in the Daldyn River basin. As a harbinger of discoveries, it was called "Zarnitsa". It was a scientific feat! Understanding the processes of formation of kimberlite bodies opened up new avenues for theoretical research and made it possible to make significant adjustments to the predictive assessment of the areas of primary and placer diamond content on the Siberian platform. The introduction of this technique led to the discovery of numerous kimberlite bodies both here and in other parts of the country. Until now, this technique, it is true, serves geologists - search engines. In the Vilyui basin, in Western Yakutia, geologists have discovered primary diamond deposits using the pyrope survey method. The Collegium of the USSR Ministry of Geology, by decision of 01.01.01, awarded the Order of Lenin for the discovery of the Zarnitsa pipe.
The initial stage of the activities of the Red Banner Amakin expedition, when the main diamond-bearing regions and the first industrial diamond deposits were discovered in five years, has already become history. At this stage of diamond prospecting, local residents (Yakuts, Evenks, Russians) provided decisive assistance to the pioneers. The first diamond on the Malaya Boutobiya River, which changed the direction of prospecting, was found by N.V. Kind, a former employee of the Geological Institute of the USSR Academy of Sciences. She owns more than a hundred scientific publications, some of which have been published abroad. became a world-famous scientist. In April 1955, as the leader of Party No. 000, she sent a detachment to field work in the area of the Irelyakh River, giving them a copy of the forecast map compiled under her leadership. Thanks to this, on the third day of the search, the team managed to find a kimberlite body in the indicated area - the Mir pipe. In the autumn of the same year, others returned to the area of the pipe and made its first geological map. A telegram with encrypted text, sent from a far corner of the Yakut taiga on June 13, 1955, has become historic. “We lit the Peace pipe. Tobacco is excellent,” said Yury Khabardin, a geologist and laureate of the Lenin Prize, to the expedition. In March 1956, from the rostrum of the XX Congress of the CPSU, it was said that in Eastern Siberia (Western Yakutia), Soviet geologists had discovered a diamond deposit. So the world became aware of the discovery of diamonds.
The history of the city of Mirny is inseparable from the diamond deposit of the Mir pipe. She gave the name to the capital of the diamond region with a population of 40,000, to an entire district that transformed the face of a vast region. Aviation played a huge role in the diamond epic.
In the period from 1954 to 1961, as a result of large complex geological and geophysical works in various regions of the eastern part of the Siberian Platform, more than 180 various kimberlite bodies were discovered. Since that time, Yakutia has been called the "diamond land".
The history of diamond prospecting in Yakutia is marked by many big names, extraordinary events, gains and losses. In it, human destinies are so closely intertwined, and even fused together, life has created and built such plots that this story is perceived as a fascinating script written by the skillful hand of a master. The circle of people who, by the will of fate, became active participants in the diamond epic was wide and diverse. Its creators, its heroes. The discovery of a diamond-bearing province with its primary and alluvial deposits is a major success for Soviet geologists and a prerequisite for the creation of a domestic diamond mining industry. The main result of the discovery of Yakut diamonds was the creation of a new diamond mining industry that did not exist before.
A new generation of geologists and other specialists of the Amakin expedition discovered a primary deposit - the Aikhal pipe (1960). In a year, Aikhal diamonds began to enter the cash desk of the Motherland. In 1969, geologists of the Boutoba expedition discovered a kimberlite body - the International pipe. Two years later, mining and preparatory work was completed and commercial mining of ore and diamonds began. In February 1975, under the leadership of geologists of the Aikhal exploration party, one of the deposits was discovered, buried under younger deposits at a depth of several tens of meters. In June 1976, exploratory drilling was already underway, an exploratory shaft was being driven.
Today, intensive exploration work in the Yakutsk diamond province continues, and the created scientific potential is used to study the patterns of kimberlite deposits.
The explored and approved reserves of diamonds in Yakutia many times exceed the reserves of industrial categories redeemed by the country's diamond mining enterprises for the entire period of the existence of the diamond industry in Russia. Realization of predicted resources will increase the deposits of explored diamonds.
Only recently in Russia many new promising deposits have been found, explored and registered, including the new diamond-bearing region of Western Yakutia. “A new kimberlite pipe has been discovered in Western Yakutia, promising to become a major source of diamond mining,” media reports say. “This is already the second diamond deposit discovered in this area. In 1994, a diamond-bearing pipe was found, named Botuobinskaya. There is a high probability of discovering diamond pipes in the Krasnoyarsk Territory.
b) Joint Stock Company "Diamonds of Russia"
Almazy Rossii - Sakha Joint Stock Company (Alrosa) is the largest concern in the country, engaged in the extraction, processing and sale of Yakutian diamonds (mining in value terms is $1.3 billion a year).
The processing of only explored diamond reserves in Yakutia, while maintaining the level of production achieved in 2000, ensures the uninterrupted operation of the mining company for 35-40 years.
To date, diamond reserves identified and explored for mining are characterized by high quality and significant volume. Inferred resources are determined with sufficient reliability and can serve as a reliable source of replenishment in the process of recovering reserves.
JSC "Diamonds of Russia-Sakha" has a significant in volume and reliable in quality mineral resource base, powerful geological exploration units equipped with domestic and imported equipment, diamond mining enterprises, unique technological processes, specialized research and design teams, highly qualified specialists in all areas of the company. The management and "think tank" of the company does not stop there. There is an active study of the company's development strategy for the future.
Many diamond mining companies in Russia, including Alrosa, have embarked on an intensification of exploration work. The industry is being reorganized, its technical re-equipment is planned, exploration organizations are being consolidated and some other measures are being taken to ensure a qualitative increase in the efficiency, mobility and efficiency of the exploration units.
Sufficient material security of mining enterprises, as well as the methodological, technological, scientific, technical and financial capabilities of the geological service, make it possible to adjust the direction of geological exploration in the near future to selectively meet the priority needs of the industry, determined by the demands of the market economy.
This company is characterized by the most stable levels of mining and the most stable financial position, which is ensured by large-scale production volumes and room for maneuver, significant financial resources.
In accordance with the plan to create opportunities for the development of the raw material base of diamond mining enterprises in the late 90s. 20th century - the beginning of the XXI century. JSC "Diamonds of Russia-Sakha" carried out the following:
1. Commissioning of the first stage of the largest mining and processing plant at the Yubileinaya pipe in 1996
2. Reconstruction of the Aikhal pipe quarries in the years, Mir in 19.
3. Commissioning in 1999 of a mining enterprise at the Botuobinskaya pipe deposit.
In addition to financing capital construction projects, considerable attention is also paid to the advanced development of areas that directly determine the volume and quality of mined diamonds in the future, such as research and exploration.
In the years The Russian diamond mining company Almazy Rossii-Sakha has invested more than $700 million in these industries, including:
For research work - 24.6 million (3.5% in total).
For exploration work - 65.5 million (9.3%).
Capital construction of production facilities - 614.2 million dollars (about 87% in total).
The company's efforts to systematically prepare the raw material base, carried out through the reconstruction and modernization of existing enterprises, as well as the construction and commissioning of new facilities, allows us to confidently look into both the near and the distant future (15-20 years perspective).
CHAPTER IV. DIAMOND IS A PROPERTY OF HUMAN CULTURE
Famous diamonds and diamonds
The word "diamond" in translation from the ancient Indian language means "one that does not break." In the beginning, warlords, kings and emperors wore diamonds. They began to be used as women's jewelry only from the middle of the 15th century. The fashion for wearing diamonds was introduced by Agnes Sorel, the mistress of King Charles VII of France. Since that time, large diamonds began to receive names. The largest diamond found was named Kulinnan.
"Culinnan"
It was discovered in the Premier kimberlite pipe in 1905 near Pretoria in South Africa. Discovered by chance by a mining inspector in a rock outcrop as a bright sparkling spot. Named after the president of the diamond mining company T. Cullinan. The facets on the surface of the stone indicated that it was a fragment of a much larger crystal.
In 1907, the Transvaal government presented the diamond to King Edward VII of England. The mass of "Kulinnan" was 3106 carats (or 621 g), and it cost 9 million pounds.
Due to its extraordinary size and one black inclusion, the stone had to be split. At the first attempt, the blade of a steel knife for splitting diamonds broke; at the second - the stone safely broke into two parts, and the master lost consciousness. The Cullinan was sawn into 105 pieces, of which the largest diamond, the Big Star of Africa (530.2 carats), which has a pear shape, was cut and set into the English royal scepter, and the Small Star of Africa (317.4 carat, oblong) adorning the crown of the British Empire. In total, 9 large and 96 small diamonds were made from the Cullinan. The "Big Star of Africa" is kept in London (Tower).
Diamond "Kohinoor"
"Kohinoor", "Koinur", one of the most famous historical diamonds, belonging to the treasures of the English crown. Legends say that it originally belonged to the ancient Indian hero Vikramaditya (56 BC). A more reliable history of the stone can be traced from the 12th century. In 1304, after the conquest of the principality of Malwa, the diamond was kept in Delhi.
The Kuinur diamond has never been sold for money. It is mentioned in the "Notes" of the founder of the Mughal Empire, Babur (Timur's great-grandson), was inherited in the Mughal dynasty. It was cut in the shape of a rose, resembling half a chicken egg cut across, its weight was 186 carats.
In 1739, Nadir Shah captured Delhi, but did not find the famous diamond there. It turned out that the owner of the stone, Muhammad Shah, constantly wore the stone in his turban. The winner offered the vanquished to exchange turbans as a sign of "eternal friendship" - so Nadir Shah became the owner of the jewel. Seeing its sparkle, Nadir Shah exclaimed: "Koh-i-nur"! ("Mountain of Light"), thus giving the name to the stone. Later, the emirs of Afghanistan were the owners of the stone. In 1813, the Lahore king Ranjit-Snngkh brought the diamond back to India by force of arms, ordered it to be inserted into a bracelet, which he wore at all receptions.
After the Sikh uprising was suppressed by the British in 1848, the Kohinoor was declared a war trophy and presented to the British Queen Victoria. In 1852 the stone was recut, after which its weight decreased to 108 ct. This diamond is set in the Royal State Crown ("Queen Mary's Crown").
Diamond "Regent"
Diamond "Regent" weighing 400 carats (80 g) was found in 1701 in Golconda (India). The English governor of the city of Madras, the former pirate Thomas Pitt, bought this diamond for pounds sterling from a local jeweler and took it to London, where he sold it in 1717 for pounds sterling to the regent of France, the Duke of Orleans. From that moment on, the diamond was named "Regent". At one time, this diamond adorned the hilt of Napoleon's sword. Now the diamond "Regent" is in the Louvre Museum in France, it weighs 27.35 g after cutting and is estimated at $ 3 million.
Diamond "Raja of Malta"
Found in 1787 on about. Borneo (modern Kalimantan), the diamond was not cut. It has a smooth pear-shaped shape and a mass of 73.4 g. The brilliance of this diamond is unique. It was believed that the fertility of the land and the wealth of the country depended on this diamond. Many believed that this diamond heals all ailments - you just need to drink the water in which it has been for some time.
Diamond "Star of the South"
The first large Brazilian diamond weighing 261.9 carats (52.4 g) was named the Star of the South. This diamond has a bluish tint and is completely transparent.
Diamond "Orlov"
"Orlov", one of the historical stones, the most famous and largest diamond in the Diamond Fund of Russia in Moscow. The mass of the stone is 199.6 carats (40 g).
It is believed that it was found in Golconda (India) at the beginning of the 17th century. Legend tells that this diamond served as an eye for the statue of Brahma in the temple of Seringapatama (Mysore state), whence it was taken at the beginning of the 17th century. kidnapped by a French soldier. According to another version, the diamond was stolen from the throne of the Persian Nadir Shah after his death (1747). In 1768, the stone was bought in Amsterdam by the Russian Count G. Orlov for gold rubles, who presented it to Catherine II, who ordered the stone to be inserted into her golden scepter.
The diamond has a slightly bluish tint, cut in the shape of a rose (an old Indian cut), in shape and size similar to a chicken egg cut across (the Kohinoor diamond had a similar shape before it was recut).
Hope Diamond
The magnificent Hope diamond weighing only 45.5 carats (9.1 g) has a deep, rare sapphire blue color of remarkable clarity. There is nothing like him in the world.
Found in the 17th century. in the mines of Golconda in India. In 1642 he was brought to France by the traveler Tavernier; the arrival of the blue diamond in Europe coincided with the outbreak of the plague brought from India. Tavernier sold the diamond (weighing 112 carats) to King Louis XIV. After cutting, a unique diamond weighing 67 carats was obtained.
There was a rumor about this stone as a fatal stone that brings misfortune to the owner. Everyone who owned it was either killed or died under mysterious circumstances. The stone was worn by the French princess Lambal - she was killed. The owner of the stone, Queen Marie Antoinette of France, was beheaded during the French Revolution. During the defeat of Versailles in 1792, the diamond disappeared, but in 1830, instead of a drop-shaped diamond, three blue diamonds appeared on sale at once, the mass of the largest was 45.5 carats. It was bought and described in detail by a passionate collector of precious stones, London banker Henry Hope, whose name he received. Hope's son was poisoned, his grandson went bankrupt.
In 1901, the Russian prince Korytovsky purchased the diamond for the Parisian dancer Ledu; subsequently, the prince shot Ledia, and then he himself was killed. "Hope" was bought by Sultan Abdul-Hamid for his concubine, but she was killed, and he himself lost the throne. The rest of the Hope owners died and went bankrupt. In 1949 Hope was bought by a New Winston millionaire; things went badly for him, and in 1958 he donated the stone to the Smithsonian Institution, where it is kept to this day. They tried to steal the diamond, but the thieves were caught by the police. Under ultraviolet rays, "Hope" does not glow blue, like most diamonds, but blood red.
Diamond "Shah"
Indian diamond "Shah" (88 ct), presented to Emperor Nicholas I by the Iranian Shah after the assassination of the Russian ambassador and poet Alexander Griboyedov in Tehran. One of the seven historical stones of the Diamond Fund of Russia.
Treasures of the Diamond Fund of Russia
Jewelry art in the territory has been known since ancient times. This is evidenced by the numerous finds of archaeologists in Transcaucasia, Central Asia, and Altai. Gold jewelry and artistic vessels of the Scythians and Sarmatians from the burials of the Black Sea, Kuban, and Lower Volga regions belong to the heights of world art. Speaking about the jewelry art of the XIX-XX centuries. It should be remembered: the Faberge *** company, which made high-quality jewelry (enamel on gold, figurines from semi-precious stones), as well as workshops that worked according to its orders (M. Perkhina). Craftsmen from the Bolin firm also worked for the Russian court.
*** "FABERGE" (Faberge), a jewelry firm in Russia in the middle of the 19th - early 20th centuries.
In 1842, Gustav Faberge opened a jewelry workshop in St. Petersburg, headed from 1870 by his son Karl Gustavovich Faberge (), transformed into a company with branches in Moscow (1887), Odessa (1890), Kyiv (1905), London (1908). Faberge products (watches, jewelry, sets, binoculars, cigarette cases, etc.), associatively interpreting historical artistic styles (Baroque, Rococo, Classicism), as well as executed in the Art Nouveau style, are marked by unique design solutions (Easter eggs with a mechanical secret), polychromy (precious and ornamental stones, gold in various texture and color combinations, multi-colored enamel coatings), careful finishing.
In Soviet times, Russian enterprises produced mass products, but some craftsmen worked on piece works that were deposited with the state in the Diamond Fund. Scientists of the Physical Institute. carried out the synthesis of fianite crystals. After a long break, major masters appeared in Russia, who set themselves the goal of restoring world fame to Russian jewelry art. As a result of the conversion of the enterprises of the military-industrial complex, new materials came into the jewelry business, such as zirconium, whose silver color gives the impression of an unearthly one in space-themed collections. The Jewelery World magazine begins to be published.
Many masterpieces of jewelry art of the XIX-XX centuries. are kept in the Diamond Fund of the Russian Federation.
DIAMOND FUND Russian Federation - the state collection of precious stones and jewelry of historical, artistic and material value, as well as unique gold and platinum nuggets. Founded in 1922
Since 1967, a permanent exhibition of the Diamond Fund has been opened in the Moscow Kremlin.
Among the seven historical stones of the Diamond Fund, there are different precious stones, but their jewelry setting always contains diamonds.
Some of the exhibits of the Diamond Fund of the Russian Federation are given in Appendix 3.
CONCLUSION
All the rocks around us that make up the earth's crust are composed of individual minerals. Each of them has its own special properties, its name, its chemical composition and appearance. A mineral in a rock is like an individual in a crowd: he has his own face, character, clothes.
The realm of minerals is truly boundless. More than three thousand minerals and mineral species are known. Many minerals are created artificially, but natural stones are more valued. Diamond crystals, cut and polished, become precious diamonds.
A whole string of rare in size and beauty stones were given by South Africa and India. The Diamond Fund of Russia stores many famous gems, including diamonds.
The main value of this stone is not only in its beauty, but in its exceptional hardness. Man put this invaluable quality of the mineral at the service of production.
Carrying out research work on the topic "Diamond - legends and reality", I discovered a lot of new things about one of the most amazing minerals, the king of minerals - diamond. I believe that the goals and objectives set before the start of work have been fulfilled.
BIBLIOGRAPHY
1. Alikberov chemistry. - M., AST-Press, 1999
2. The planet was discovered together. - M., Nauka, 1971
3. Kulikov - reference book of semi-precious stones. - M., SME Publishing House, 2002
4., “North-East of Russia. Problems and Priorities of Socio-Economic Development”. Article in the newspaper "Geography", a weekly supplement to the newspaper "First of September", No. 31 (166) / 1996
5., "Carbon in minerals". Article in the theoretical and scientific-methodical journal "Geography at School", No. 5/2004
6. In search of the blue land. - M., Nauka, 1982
7. Milashev. Legends and reality. - Leningrad, Nedra, 1981
8. "Diamond-Brilliant Complex of the World". Article in the theoretical and scientific-methodical journal "Geography at School", No. 7/2004
9. Website http://www. klopotov. *****/minerals
10. Treasures of the Diamond Fund of the USSR. Exhibition catalog / Compilers, etc. - M., Fine Arts, 1972
11. Fersman mineralogy. - M., Detgiz, 1953
12. I know the world: Children's Encyclopedia: Treasures of the Earth. - M., AST, 2003
GLOSSARY OF TERMS
ABRASIVE MATERIALS(abrasives) (from Latin abrasio - scraping), substances of increased hardness used in a massive or crushed state for mechanical processing (grinding, cutting, abrasion, sharpening, polishing, etc.) of other materials. Natural abrasive materials - flint, emery, pumice, corundum, garnet, diamond, etc.; artificial - electrocorundum, monocorundum, silicon carbide, borazone, elbor, synthetic diamond, etc.
DIAMOND, mineral, crystalline cubic polymorphic modification of native carbon.
DIAMOND FUND OF THE RUSSIAN FEDERATION, a state collection of precious stones and jewelry of historical, artistic and material value, as well as unique gold and platinum nuggets.
BALLAS, a kind of diamond, small rounded radiant aggregates.
BOARD(Dutch. boort), low-quality diamond crystals and aggregates, unsuitable for cutting. They are used as abrasive materials.
DIAMOND(from the French brillant, lit. - brilliant), a flawless gem diamond, the special artificial cut of which brings out its brilliance to the maximum. Due to the high dispersion in reflected light, the diamond "plays" with all the colors of the rainbow. The mass of a diamond is measured in carats (0.2 g).
GEMMOLOGY(from lat. gemma - precious stone and logos - word, doctrine), studies precious and semi-precious stones, mainly their physical properties, chemical composition, decorative artistic merits, mineralization of deposits, as well as processing technology.
GOLCONDA, state in India, on the Deccan, in the 16-17 centuries. It was famous for weaving and other crafts, diamond mining.
GRAPHITE, mineral, the most common and stable polymorphic hexagonal modification of carbon in the earth's crust.
DISPERSITY, characterization of particle size in disperse systems. The measure of dispersion is the ratio of the total surface of all particles to their total volume or mass.
CARAT,
1) submultiple unit of mass, used in jewelry. Marked as car. Metric carat - 200 mg - 2 10-4 kg.
CARBONADO, type of diamond fine-grained porous aggregates of gray or black color. Polycrystalline carbonado is synthesized on an industrial scale.
KIMBERLY, a group of diamond deposits in South Africa. Developed since 1867. Area up to 195 thousand m2; includes 15 kimberlite pipes. The main production center is Kimberley.
KIMBERLITE, brecciated ultramafic rock that fills the blast tubes. Consists of olivine, phlogopite, pyrope and other minerals. Black, with a bluish and greenish tint. More than 1500 kimberlite bodies are known, of which about 8-10% are diamond-bearing. The main diamond-bearing kimberlites in South Africa and the Russian Federation.
ROAD DEPOSITS, deposits of minerals that have not undergone changes (bedrock); are opposed to placer deposits of the same minerals.
MOHS SCALE(mineralogical scale of hardness), a set of reference minerals for determining relative hardness by scratching. 10 minerals were taken as standards, arranged in order of increasing hardness: 1 - talc, 2 - gypsum, 3 - calcite, 4 - fluorite, 5 - apatite, 6 - orthoclase, 7 - quartz, 8 - topaz, 9 - corundum, 10 - diamond. It should be borne in mind that the difference between the properties of the first standard substances of the Mohs scale is much smaller than that of the latter substances, i.e., the scale is non-linear. It was proposed in 1811 by the German mineralogist F. Moos (Mos; F. Mohs).
CUTTING,
1) giving the jewelry stone a geometrically regular or asymmetric polyhedron shape by grinding and polishing.
2) A combination of facets of various shapes and sizes, applied to the surface of the stone. Cut forms: rose (from 12 to 72 facets), semi-brilliant (from 12 to 32), brilliant (from 48 to 240 and more), stepped, wedges, mixed, cabochon.
ARMORY in the Moscow Kremlin,
1) the central state institution in Russia, in the XVI - early XVIII centuries. - a place for the manufacture, purchase and storage of weapons, jewelry, palace household items.
2) One of the oldest Russian museums, founded in 1806 (the building was built in 1844-51, architect), since 1960 as part of the State Museums of the Moscow Kremlin; collection of decorative and applied arts of Russia, Zap. Europe and a number of eastern countries of the 5th - early 20th centuries. (fabrics, clothes, dishes, weapons, armor, royal thrones and regalia, etc.).
POLISHING(polishing) (German Polieren, from Latin polio - I make smooth), in stone processing, polishing is done by rubbing the surface with the finest powder (for example, tin oxide) manually or on specialized machines.
PRIME(Premier), a diamond deposit in South Africa. A kimberlite pipe with an area of 880x500 m. The world's largest diamond "Cullinan" weighing 3106 carats was recovered (1905).
ALLOWER DEPOSITS(placers), accumulations of gold, platinum, diamonds and other valuable minerals in loose deposits formed due to the destruction of primary deposits. By origin, alluvial, deluvial, eluvial, marine and other alluvial deposits are distinguished.
SYNGONY,(from the Greek syn - together and gonia - angle), the classification division of crystals on the basis of the symmetry of the unit cell of the crystal, is characterized by the relationship between its edges and corners.
TAPEWORM,(French solitaire, lit. - lonely), a large diamond set in a ring, brooch, etc. separately, without other stones.
CLEAVAGE, the ability of crystals to split upon impact (or other mechanical action) along certain cleavage planes.
STRAZ(German Strass, named after the inventor, glass maker and jeweler of the late 18th century. J. Strass), an artificial stone made from crystal with an admixture of lead, similar in brilliance and play to precious stones; counterfeit gem. The most famous were rhinestones made of colorless glass - under "diamonds". "Emeralds" were created by an impurity during the melting of chromium oxide, "topazes" - iron oxides, "amethysts" - cobalt oxides.
EXPLOSION TUBE(diatreme), a tubular channel formed during the breakthrough of gases through the layers of the earth's crust and filled with brecciated rocks, up to 1 km in diameter. They are often filled with diamond-bearing breccia - kimberlite (for example, on the Siberian platform in Russia, South Africa, India, etc.).
zirconia, a group of synthetic single crystals based on zirconium or hafnium oxides. Known as imitation diamond.
PHYSICAL INSTITUTE them. RAS (FIAN), organized in 1934 (leads its history from the Physical Cabinet of the St. Petersburg Academy of Sciences, founded in 1725) in Moscow.
GRINDING(grinding) (from Polish szlifowac - sharpen, polish, grind), surface treatment of products made of various materials (metal, wood, glass, ceramic, etc.) with an abrasive tool on grinding machines. Grinding produces surfaces with low roughness.
Schlich,.[German] Schlich], a residue of particles of minerals of a large specific gravity, obtained by washing sands and other loose rocks.
Attachment 1
Map of world diamond mining
Appendix 2
Diamond complex of the world
World Diamond Processing Map
Annex 3
Treasures of the Diamond Fund of the Russian Federation
Great imperial crown
Diamonds, ruby, silver, pearls. 1762 Posier
Imperial scepter
Gold, Orlov diamond, diamonds, silver, enamel. 1770s
The cabochon-cut Orlov diamond (199.6 carats) was brought from India and presented by Count G. Orlov to Empress Catherine II. It is one of the seven historical stones of the Diamond Fund of Russia.
The Indian diamond "Shah" (88 ct.) was presented to Emperor Nicholas I by the Iranian Shah after the assassination of the Russian ambassador and poet Alexander Griboyedov in Tehran. One of the seven historical stones of the Diamond Fund of Russia.
Bracelet
Diamond, gold, emeralds, enamel.
Second quarter of the 19th century
Flat portrait diamond (about 25 ct.) of rare purity and size. This is the largest portrait stone in the world, one of the seven historical stones of the Diamond Fund of Russia.
Brooch
Emerald, diamonds, gold, silver. Mid 19th century
In the center of the brooch is a step-cut Colombian emerald from the 15th or 16th century. Around - a frame in the form of diamond grape leaves. Emerald is one of the seven historical stones of the Diamond Fund of Russia.
Brooch
Sapphire, diamonds, roses, silver, gold. Mid 19th century.
Brooch with an old Indian-cut Ceylon sapphire - the largest and most beautiful in the world - in an openwork setting of large and small Brazilian diamonds and roses.
Sapphire is one of the seven historical stones of the Diamond Fund of Russia.
Imperial power
Gold, diamonds, sapphire, diamond, silver. 1762
Belonged to Empress Catherine II. Orb in the form of a golden polished ball topped with a diamond cross mounted on a large Ceylon sapphire weighing 200 carats.
At the intersection of diamond belts is a large diamond weighing 46.92 carats.
Star of the Order of St. Andrew the First-Called
Diamonds, roses, silver, enamel. gg.
Marshall Star. 20th century