What can you tell us about the diamond?

Ballas (ballas) – variety flanks: radial-radiant aggregates of microcrystalline diamond of round shape; usually free of foreign material
Board (boart, bort) – opaque, black and gray microcrystalline diamond aggregates, which are used as abrasive powder
Diamond (brilliant) – cut gem quality diamond
Impact diamond (impact diamond) – diamond, which is formed during an impact solid-phase transition from graphite and other forms of carbon; inherits the appearance of the original grains and aggregates, has a gray, yellow and black color; characterized by a polycrystalline structure, the presence of a large number of defects in the crystal structure, and the possible presence of lonsdaleite
Carbonado (carbonado) – microcrystalline dense or porous diamond aggregates of grayish or black color; found in placers
Synthetic diamond – diamond, obtained artificially from non-diamond carbon and carbon-containing substances, has the crystalline structure and basic chemical composition of natural diamond (NDD)
Rhinestone (stras) – glass imitation of a diamond (brilliant) or other cut gem; named after the German inventor I. Strass
Yakutit (yakutite) is a term used to designate polycrystalline impact diamonds from placers in Northern Yakutia; it was introduced by Chumak M.A., Bartoshinsky Z.V. (1968)
(Unless otherwise indicated, source – VSEGEI Geological Dictionary)

Polymorphism: The diamond mineral is polymorphic with graphite, lonsdaleite, tartarosite and chaoite.
Syngony: Cubic
Composition (formula): C

Color: Usually colorless with barely noticeable color tints; can be yellow, brown, mauve, green, blue, milky white and gray to black (VSEGEI Geological Dictionary)

Trait color: White (ALL); no trait (mindat.org)
Transparency: Opaque, transparent, translucent
Cleavage: Perfect
Fracture: Uneven, conchoidal
Gloss: Diamond, bold
Hardness: 10 (Mohs scale standard)

Density (specific gravity), g/cm3: 3,511 – measured; 3,515 – calculated (RRUFF) 3,50-3,56; at the edge and carbonado due to porosity it can decrease to 3,00 (VSEGEI) 3,47-3,56 – measured. (for carbonado 3,01-3,47); ~3,511 – calculated from X-ray diffraction patterns (BSE)

Fragility: Fragile (RRUFF)

Special properties: Perfect cleavage (RRUFF), average over the octahedron (Smolyaninov N.A., 1972, p. 295)
Fluorescent and phosphorescent; triboelectric; has the highest thermal conductivity of all known substances (RRUFF).
Diamond luminesces in ultraviolet light in blue, cyan and yellow, yellow-green, orange, pink and red. With rare exceptions, it luminesces under the influence of X-rays and cathode rays, and when bombarded by fast particles (VSEGEI).
The transparency of diamond depends on microscopic inclusions of graphite and other substances. High dispersion (0,063) causes the play of light in diamonds (VSEGEI).
In air it burns at 850°C (VSEGEI).
Before the blowpipe, the grain does not change, but in the form of a fine powder it burns slowly, without a flame. Aluminum does not leave a mark on the wetted surface of a diamond, unlike other minerals, on which it leaves an indelible mark (Smolyaninov N.A., 1972, p. 295).
Electrical conductivity is weak, semiconductor type, and in pure varieties it is completely absent. Diamond exists in nature and outside its stability field, remaining in a metastable state for a long time (Betekhtin A.G., 2007, p. 12).
Diamond transmits ultraviolet and infrared rays. Non-conductor of electricity. At a temperature of about 1850°C in a void it turns into graphite (Smolyaninov N.A., 1972, p. 39).
Diamond is a diamagnetic (DSB).

Diamond differs from similar-looking quartz in its high hardness, cleavage, brilliance, crystal shape, isotropy, indecomposability in hydrofluoric acid, and luminescence.
If you draw with an aluminum stick on the wetted surface of a diamond, then the aluminum does not leave any trace; on other minerals – quartz, topaz, as well as on glass and enamel, indelible shiny silver lines remain.
A diamond is clearly recognized when immersed in water: the diamond protrudes sharply due to the large difference in the refractive indices of it and water. In this way, diamond can be easily distinguished from quartz and other relatively weakly refractive minerals (Smolyaninov N.A., 1972, p. 40).

Octahedral, rhombic dodecahedral, cubic crystals; granular; porous joints; rounded grains with dissolution figures; radial fibrous aggregates. Twins according to the spinel law (VSEGEI Geological Dictionary).
Diamond crystallizes into cubic systems. The most important crystallographic forms of diamond: flat-faced – octahedron, rhombic dodecahedron, cube and various combinations thereof; curved – dodecahedroids, octahedroids and cuboids. There are complex combined forms, intergrowth twins according to the spinel law, germination twins and granular aggregates. The crystal faces are usually covered with growth and dissolution patterns in the form of individual protrusions and depressions (BSE).

Diamonds are found in meteorites; impact rocks associated with meteorite craters (astroblemes); in kimberlites and xenoliths of deep mantle rocks of peridotite and eclogite composition located in them; in lamproites, some minettes and metamorphosed ultramafic rocks; in various metamorphic rocks; as well as in placers of different age and genesis (alluvial, colluvial, eluvial, coastal-marine, proluvial and others) (VSEGEI Geological Dictionary)
Igneous – due to the main igneous rocks in the explosion pipes; cosmic – in meteorites (Smolyaninov N.A., 1972, p. 40)

Precious stone. Abrasive, cutting and grinding material; in particular, material for bits of drilling tools (Smolyaninov N.A., 1972, p. 39)
Jewelry diamonds are usually used in the form of jewelry, and also as a safe investment.

Interesting Facts

The absolute hardness of diamond is 1000 times higher than the hardness of quartz and 150 times higher than that of corundum (Betekhtin A.G., 2007, p. 188).

For the discovery and exploration of the Efimovskoye and Rybyakovskoye diamond deposits in the Perm Territory, Minister Kobylkin awarded six geologists with the “Discoverer of the Deposit” badge on August 24, 2020. One of them, V.R. Ostroumova (1952-2003) – posthumously.

Diamond is a crystalline modification of pure carbon, formed in the deep interior of the Earth, in the upper mantle at depths of more than 80-100 kilometers, at exceptionally high pressure and temperature. It is the most precious stone, the hardest and most wear-resistant mineral, the most brilliant and timeless gem. The history of diamonds goes back thousands of years, but even today diamonds attract millions of people with their magical beauty.

At all times, this fascinating and unique stone has attracted people. “It remains unharmed in the strongest fire, it is the light of the sun, condensed in the earth and cooled by time, it plays with all colors, but itself remains transparent, like a drop of water. “- they wrote about diamonds in ancient times. The first mention of human use of diamonds dates back to India and appeared approximately three thousand years BC. Diamonds pass like a sparkling thread through the fabric of existence, through the history of mankind, disappearing for a while and reappearing to illuminate the most incredible and bizarre legends with their mysterious radiance. “The greatest price among all human things, and not only among precious stones, is the diamond, which for a long time was known only to kings, and even then to very few,” wrote the ancient Roman scientist Pliny the Elder in 79 AD. in his treatise “On Natural History”.

The Greeks called it “adamas” or “adamantos” – invincible, indestructible, insurmountable; Romans – “diamond”; Arabs – “almas”, the hardest; ancient Jews – “shamir”; the Hindus called him “Fariy”. The Old Russian literary monument, “Izbornik” of 1073, equally uses the terms “adamas” and “adamant”, and “Walking across the Three Seas” by Afanasy Nikitin (1466-1472) for the first time, and forever, “legitimized” in Russian the name is “diamond”. In ancient India, it was believed that diamonds were formed from the five principles of nature – earth, water, air, sky and energy. In India, the diamond was deified and turned into a fetish. He was endowed with many mythical abilities, such as healing from diseases, protection from evil spirits and simply enemies, from wounds, the evil eye, damage; declared to bestow clairvoyance, the ability to predict.

The metric carat used to measure the weight of diamonds is 0,2 grams or 200 milligrams. Diamonds weighing more than 15 carats are rare; diamonds weighing hundreds of carats are the greatest rarity. Some stones receive their own names, world fame and a strong place in history. Read more about historical diamonds. Currently, global diamond production is about 130 million carats. Read more about diamond mining. The main use of natural diamonds is in jewelry, but not every diamond can be made into a diamond. Of course, about 15% of mined diamonds are considered jewelry, another 45% are considered near jewelry, i.e. inferior to jewelry in size, color or clarity. Until the end of the XNUMXth century, only the upper classes owned diamonds, but in the XNUMXth century large diamond deposits were discovered, and increased production made them more accessible to buyers. However, even today, diamonds are not available to everyone, and people still view diamond ownership as belonging to the most successful part of society.

The sparkle and beauty of a diamond are fully revealed only after cutting. For a long time it was believed that L. van Berkem from Bruges at the end of the 15th century. developed a method of precise symmetrical cutting (still used today), which consists of grinding the stone on an iron wheel, onto which a mixture of diamond powder and oil is applied. Now the existence of this master is being questioned. The above method is believed to have been developed in India. Previously, it was also believed that diamond cutting was invented by the Italian lapidary Vincenzo Peruzzi at the end of the 17th century, but this opinion also turned out to be erroneous. Therefore, there is no consensus among historians about where and when the diamond cut appeared.

Diamond (from the French brillant – brilliant), a diamond that has been given a special shape through processing, the so-called brilliant cut, which maximizes the optical properties of the stone. Over the course of centuries of trial and error, cutters have learned to use the refractive index of the stone in such a way as to re-reflect the light entering the stone from the side of the crown on the edges of the pavilion and scatter it in different directions. Thanks to the dispersion of light inherent in diamonds, one can observe the play of the diamond in the form of rays of all colors of the rainbow. Learn more about diamond cutting. The word “diamond” is actually the name of the type of cut, not the material. But in the case when we are talking about a diamond cut from a diamond, the name of the material may be omitted. In this case, “diamond” means both the substance and the type of cut. The word “diamond” is used when referring to the material itself, substance, or when talking about rough diamonds.

A rough diamond is the raw material from which cutters will make a diamond, and jewelry craftsmen will use it to create a luxury product. Diamonds, like fingerprints, are unique – no two stones are completely identical. Diamonds, on the contrary, are made according to strictly defined rules. There are diamonds, for example, yellow or black, designer cut shapes, which are subject to fashion, and the demand for them is variable. But the classic diamond stands above fashion, and the demand for it has not changed over the years. The statement “Diamond is forever”, i.e. “A Diamond is Forever” not only illustrates the invariably high place of diamonds in our society and the connection of these stones with eternal human feelings, but also their unimaginably ancient age. The fact is that the scientific methods used to determine the age of minerals and rocks give diamonds an age of one and a half to three and a half billion years. We can say that diamonds are older than everything that surrounds us, and their age is comparable to the age of our planet.

Diamonds, as carriers of unique hardness and other interesting properties, are objects of close attention of scientists; they are both an object of research and a valuable material for use in technology. There are also specialists – gemologists, or precious stone experts. Over the past decades, gemologists have been developing scientific methods for determining the authenticity of rough and polished diamonds, objective systems for their evaluation, and recommendations for cutting diamonds. Read more about diamond examination. However, it is not easy for a potential buyer to navigate this large amount of knowledge, especially if he is looking for simple recommendations that would allow him to navigate the world of diamonds and develop the right course of action in the market. Much of the information that allows professionals to make money selling diamonds has been developed over many years and is a trade secret. However, today, in the age of information technology, information is becoming much more accessible, and for any person who wants to become an expert, a qualified consumer, there are no former restrictions. Advice to consumers.

Truly, the diamond has no competitors – it is the undisputed favorite in the world of precious stones and jewelry. However, no matter how wonderful properties diamonds have, when purchasing products with this stone, you can never rely on chance. An unprepared person, when dealing with precious stones, is often doomed to failure. It is worth approaching the purchase of such a serious stone well prepared. A future buyer can learn to understand a stone as a “personality” and evaluate such important characteristics as color, clarity, cut, its play and brilliance, weight, and learn to relate all this to its price. Diamonds are a lot like people. Almost each of them has disadvantages that you just need to be able to discern (there is practically no ideal), and some individual advantages, for example, high quality cutting or polishing, a unique color. The individuality of diamonds remains despite the standards that guide the cutters, since this individuality is inherent in diamonds – unique natural creations. Understanding the individuality of diamonds allows you to choose the most suitable stone. The process of searching and choosing a diamond does not have to be reduced to a visit to the nearest jewelry store; it can become an exciting event, a journey in which new knowledge, new impressions and new experiences await everyone. Go to the forum.

photographs used by De Beers and the magazine “Around the World”