Community > Forums > Metals & Minerals Knowledge > Diamond (1)
Post a topic Post a survey Forum Guidelines

Diamond (1) 2 replies,978 views


 Diamond Introduction

 1, the mineral name "diamond", the English as a Diamond, from the ancient Greek Adamant, meaning hard physical inviolability, is recognized as king of precious stones.  The chemical composition of the diamond has 99.98% of carbon.  In other words, the diamond is actually a very high density of carbon crystals.

 2 Mohs hardness of diamond: 10 is the highest natural mineral hardness.  But do not think that high hardness of diamonds, you will never break.  In fact, diamonds are also very high brittleness, the collision force will shatter.

 3 stone diamond is based on its original shape, to cut into various shapes of diamonds.  Among them, eight welcomed by the shape: round, oval, olive tip, heart, pear, square, triangular and beryl shape.  Round diamonds, is the most common shape.

 4, the diamond is a natural mineral.  The main origin of diamonds is Australia, South Africa, India; the United States, India, Israel, Belgium is cut diamond processing base.  Particularly in Belgium, is a recognized crafted diamond trading center.

 5, buy a diamond must be re-examination

 The chemical composition of diamond

 The chemical composition of the diamond is carbon, which is the only gem composed of a single element, are equiaxed crystal.  Mostly octahedral crystal form, rhombic dodecahedron, tetrahedron, and together they form.  Pure colorless diamond, while the trace elements show different colors mixed.  Strong adamantine luster.  Refractive index 2.417, the dispersion medium, 0.044.  Homogeneous body.  Thermal conductivity of 0.35 card / cm. Sec. Degrees.  With a thermal conductivity meter test, the reaction is most sensitive.  Hardness of 10, is the hardest known mineral, quartz absolute hardness is 1000 times 150 times corundum, fear, hit after heavy hit broken along its cleavage.  A cleavage completely.  Density of 3.52 g / cc.  Diamond has a luminance, sunlight, the night pale blue phosphorescence can be issued.  X-ray irradiation, issue sky-blue fluorescence.  Chemical properties of diamonds is very stable at room temperature is not easy to dissolve in acid and alkali, acid does not produce its effect.

 Similar to the diamond and precious stones, synthetic diamond distinction.  Substitute for the market common stones or fake stones are colorless, colorless spinel, cubic zirconia, strontium titanate, yttrium aluminum garnet, yttrium gallium garnet, synthetic rutile.  First synthetic diamond in 1955, successfully developed by the Japanese, but not mass production.  Than natural diamonds, synthetic diamonds because of the high cost of synthetic diamond so rare on the market.  Diamond with its unique hardness, density, dispersion, refractive index differences can be with similar gems.  Such as: Fangzuan cubic zirconia and more colorless, strong dispersion (0.060), strong luster, density, 5.8 grams / cubic centimeter, weigh heavy hand being obvious.  Yttrium aluminum garnet dispersion soft, it is difficult to visually distinguish the diamond.

 It has become the people they can have, people wear precious stones.  Diamond's culture has a long history, more people today see it as a symbol of love and loyalty.

 Reasons for the formation of diamonds

 Modern science and technology, the means for exploring the formation of the diamond provides a new idea and method.  Diamond is the world's hardest, most simple ingredients gem, which is composed of carbon, with a cubic structure of the natural crystal.  The treasure map diamond components and our common coal, pencil lead is basically the same ingredients and sugar, carbon at a higher temperature, pressure, the crystallization of graphite (black), and in the high temperature, high pressure and restore the environment ( Generally, is a hypoxic environment) in the crystal for the precious diamonds (white).  In order to facilitate understanding of the origin of diamonds, the first look at the original rock that contains diamonds.

 Since diamonds were discovered in India since we have heard the people in the river, riverside picked up the story of the diamond, which is due somewhere in the river upstream of the original rock containing diamonds, are weathered, broken, diamonds were taken with the flow to downstream areas, heavy diamond buried in the gravel.  What is the original rock of diamonds?  People in South Africa in 1870 on a farm in the loess dug diamonds, since diamonds dug from the river bed moved to the loess, the loess below the dark blue is hard rock, it is the original rock of diamonds - the Kimberley rock (kimberlite).  What is kimberlite?  Kimberlite is formed in the deep Earth, contains large amounts of carbonic acid gas and other volatile components of alkaline ultramafic volcanic rocks, which often contain rocks from the Earth's deep peridotite, eclogite fragments, mainly minerals, including olivine, phlogopite, carbonate, pyroxene, garnet and so on.  Studies have shown that the formation of the Kimberley magma deep in the earth 150 kilometers below.  Because of this rock was first discovered in Kimberley, South Africa, so named by the names.

 Another said the original rock that contains diamonds lamproite (lamproite), it is a peralkaline volcanic magnesia, mainly leucite, the formation of volcanic glass, may contain pyroxene, olivine and other minerals, typical origin of Western Australia Argyll (Argyle).

 Scientists have been mining diamonds from around the world on the native mineral inclusions and its study found that the diamond formation conditions are generally the pressure in the 4.5-6.0Gpa (equivalent to 150-200km depth), temperature of 1100-1500 degrees Celsius.  Although in theory, the diamond can be formed in various periods of Earth's history / phase, and exploitation of mines present, most diamonds were formed at 33 million years ago and the 12-17 million years these two periods.  Such as the number of diamonds in South Africa the age of about 4.5 billion, indicating that the diamonds in the earth had already begun shortly after the birth of the deep Earth crystal, diamond is the world's most ancient gems.  Diamond formation requires a long historical process, which mainly produced from the diamond stability in the ancient Earth can confirm the mainland.  In addition, stars on the planet extraterrestrial impact, resulting in transient high temperature, high pressure, but also the formation of diamond, such as the USSR Academy of Sciences report in 1988 found a diamond in meteorites, but this effect is not the economic value of the diamond formation.

 Rare diamond rocks mainly in two categories, one is olive rock, one is eclogite, but only the former has economic significance.  Peridotite with diamonds, so far found two types: kimberlite (kimberlite) (the name comes from South Africa was a place name - Kimberley) and lamproites (lamproite), both in the volcanic rocks are role of the elected, the rocks formed in the depths of the earth were brought to the surface by volcanic activity or shallow earth, which mostly magmatic rocks tube output, so called "tube Mine" (the original ore.)  Kimberlites contain diamonds or lamproite exposed on the surface, through the wind and rain and other outside forces, but the role of the Earth weathered, broken, washed in water, the broken drill is the original rock was brought to bed with, and even Coast Strip off the product, the formation of alluvial sand deposits (or secondary deposits.)

 Why expensive diamond

 The reason why diamonds are human beings known as the "king of precious stones", and become the most expensive varieties of precious stones, in addition to the charm and the quality of the diamond itself relevant, but also to the detection of diamond deposits and processing are closely related.

 1, the intrinsic charm of the quality of the diamond

 As precious stones, must have beauty, durability and rare these three elements.  Diamond is the only set of the highest hardness, high refractive index and high dispersion in one of the varieties of precious stones, precious stones of any other species are unparalleled.  This treasure of treasures, rare in the Han, deserved to become the most expensive in the.

 2, culture has a long history of diamonds

 Since ancient times, diamonds have been considered by human power, dignity, status and a symbol of wealth.  The indestructible, invincible, eternal constancy and perseverance masculine quality, always pursue the goal of mankind.  It has potential, great cultural value.

 3, the diamond deposits to explore difficult and costly

 Search for diamond deposits, not as legendary as you can accidentally fall fall that found a diamond deposit.  The search for diamond deposits often takes decades or even centuries of hard work and labor, and costly.  If the former Soviet Union in Siberia original diamond deposits to explore, since 1913, after 18 years of hard, only to find; Botswana, "Euler" primary deposit, costing $ 32,000,000, after 12 years of struggle, excavated; near years in northwestern Canada, primary diamond deposit discovered, it is through the hard work of generations of geologists, costing at least hundreds of millions of dollars to find.

 4, a small number of diamond deposits, low grade gem diamond deposits

 The number of the world's diamond deposits, and if with iron, copper and gold mine compared to the number, it can be said to be very little, few.  In the exploitation of the diamond, an average of only 20% to gem, while the remaining 80% can only be used for industry.  But 20% of the value of gem-quality diamond is equivalent to 80% of the industrial diamond 5 times.  The world's annual output of about 100 million karats of diamond, gem about 1,500 million carats, and processed into a treasure map network diamond drilling stone about 4 million kt (equivalent to 800 kg.)

 Some rough statistics found to be 1 carat (0.2 grams) had a good polished diamonds, you need to dig about 250 tons of ore.

 5, the exploitation of vast size, extremely difficult

 The exploitation of diamond deposits, it can be said is a huge, but careful work in every possible way.  Mining process, both the need for full exploitation of ore containing diamonds, but also cautious to ensure that the ore particles of rough diamonds in good condition.  Will lead to improper exploitation of the enormous economic losses.  Both open-pit mining, and underground mining, and the scene is a huge project momentum, investment in human and material resources is unimaginable.

 6, diamond processing complex, large work

 Of the mined ore crushing and sorting well after the deposit is not the same as the other metals, can be put into large quantities of smelting, but every grain of rough diamonds on a case-by careful and meticulous analysis of grain in order to determine the next Cutting programs to ensure its weight, clarity and style.  This often requires the physical optical properties of the diamond itself, a full understanding has considerable experience of the personnel.  General steps: design marking; split drill; saw drill; car drilling; burr; cleaning grading.  Each step which also includes a plethora of small programs.  Each small step requires sophisticated technology and rich experience.  Take the highest in the world of the Cullinan diamond, the original stone 3,106 carats, three experienced and superior skills of craftsmen, working 14 hours a day, consuming a total of 8 months before it split into four large drilling and 101 gems.  Some of the world's leading diamond processing, often only the design should take months, even 1-2 years.

 7, to consumers, the experience of a range of diamond

 According to some preliminary statistics, a diamond, from its mining, sorting, processing, grading, marketing, and finally sold to buyers in the hands, some involving more than 200 million people, a diamond ring is a natural God and more than 200 million people great efforts that the diamond is extremely precious resource and in which the origin of the world diamond

 World diamond reserves and production profile:

 Currently, the proven reserves of natural diamonds of about 2.5 billion carats, of which 650 million karats in Australia, Zaire 550 million karats.  Diamond mining at the current level of reserves in existing mining only 25 years, but with increased levels of exploration technology, every year there are new mines discovered in recent years, the diamond reserves in Canada increased significantly.

 Since the diamond mining has been a total of about 350 tons of diamonds mined, only 1.75 billion kt, and now mining diamonds in the world each year the world's 90 million -1 million carats of diamond resources distribution, which account for 17% -20 gem%.  20% of the value of gem-quality diamonds is equivalent to 80% of the value of industrial-grade diamond 5 times.

 1, diamond-producing countries

 Throughout the world diamond production, has more than thirty countries have diamond resources, the annual output of about one hundred million karats.  Yield the top five countries are Australia, Zaire, Botswana, Russia, South Africa.  The five countries of the world diamond production about 90% of diamond production.  Other diamond producing countries of the Congo (DRC), Brazil, Guyana, Venezuela, Angola, Central Africa, Ghana, Guinea, Ivory Coast, Liberia, Namibia, Sierra Leone, Tanzania, Zimbabwe, Indonesia, India, China, Canada .

 China's proven reserves and production of diamond in the world ranking of 10 or so, the annual output of 20 million carats of diamonds Wafangdian mainly in Liaoning, Shandong and Hunan Mengyin Yuanjiang basin, which is currently the largest in Asia, Liaoning Wafangdian diamond mine.

 2, the best diamond-producing countries

 For the diamond and gem diamonds rough proportion, the best diamonds from alluvial deposits in Namibia, mined diamonds.  Natural weathering of these diamonds carry through to the beach, walk up to 1,000 miles.  After this vulnerable part of the journey diamonds are separated.  Depositional environment in a particular grain size of diamonds of different shapes for different distribution of certain rules in rock layers.  The gem diamond mining area of up to 97% quartz.  Cutting a good diamond ring on the surface, which is difficult to differentiate from producing countries and mining.

 Diamond mining output has any good, the bad.  Get the best diamond mining and diamond than the worst output of Namibia, Namibia alluvial diamond deposits is not necessarily like.

 3, changes in the diamond fields

 India is the world's first discovery of diamonds in the country, 3000 years ago, India is the only diamond-producing area.  Since 2,500 years ago to the early 18th century India Krishna River, Penner River and its tributaries is the world's only diamond output place, the history of many famous diamonds such as the Mountain of Light (kohi-noor), Orlov (orloff ) and large Mughal (great mogul) are from India, but India's diamond production is small.

 To the discovery of diamonds in Brazil in 1725 and mining, to replace the India, Brazil became the world's most important diamond-producing area.

 After 1867, South Africa, found a large number of alluvial sand deposits and kimberlite tube made of native South Africa as the world's most important diamond producing countries, a long period of its production in the world, and thus created a new era in the diamond industry.  In 1905, in South Africa's sub-Azar discovered the world's largest kimberlite Yanyan tube - Puliemier rock cylinder, and in this the largest diamond found (Cullinan diamond).  Currently, South Africa has the world's largest output, and the most modern Pooh Tia diamond mine.  South African diamonds are large, good quality, 50% of the diamonds are to cut its production was not as Australia and other countries, but output has been highest in the world.

 Since 1979, Western Australia porphyry contains potassium and magnesium found in diamond since 1986, Australia's diamond production has been home dominance, but the gem only 5% of its production.  Diamond mainly Western Australia, Australia New South Wales, bingara and copeton, particularly Argyll (argle) deposit reserves of 550 million karats.

 Botswana is rich in high-quality diamond, gem, 50%, the output ranks first in the world.  Botswana's diamond kimberlite from surface mining, a huge rock mines are orapa tube (1967), letihakena rock cylinder (1977) and jwaneng diamond mines (1982), three mine production in 1989 over 1500 million carats.

 Russia's diamonds are mainly distributed in central Siberia, Yakutia region, the area to find more than one hundred diamond-bearing kimberlite tube, 1988, Russia closer to Europe to find new diamond mines in the vicinity of another.  At present, Russia at 12 million karats diamond production of about half of the gem.  Over the years the formation of an independent Russian diamond mining processing and marketing system, a large number of its diamonds, excellent quality, good uniformity in the market is highly competitive.

 A few years ago discovered in northern Canada reported that a large number of kimberlites, diamond production after a few years can account for 10% of world production.

 4, the world's first diamond mine

 July 16, 1871, adhere to the depths of the excavation team Shangkuli Fort extraction was successful partnership, they occupied dozens of square meters of land, has been The depth of excavation, in this day has finally found their dream of diamonds.  Also the world's first diamond mine was born.  Named "Library Power Johannesburg mine," also called "new wave of mine."

 5, South Africa's diamond mines

 Diamond said that people will think of to live in South Africa.  South Africa's output of diamonds are known for large particles, good quality and famous.  From the quartz mining rough diamond out of 50% can be achieved in the gem.  Fifty years ago, South Africa's diamond production in the world, so often customers will ask "Fengyun South Africa diamonds?" As time goes by, South Africa's diamond production decreased year after year.  1987, South Africa, production of 10 million karats of diamonds is about 10% of world production.

Share to:

Re: Diamond (1)
good one...
Re: Diamond (1)
thanks a lot really wonderful insight.

Forum Guidelines

For general customer inquires, please contact Alibaba Service Center.
To lodge a dispute/complaint, please visit our Complaints Center.
For general AliExpress customer inquiries, please contact AliExpress Customer Support.
If any posts corresponding to the categories above are located in the Forums, they will be deleted without prior notice.