Diamond Of California Business Information, Profile, and History

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A naturally occurring form of crystalline carbon formed at high pressures and temperatures deep in the Earth's crust. It is found in volcanic pipes, called kimberlites, and in alluvial deposits. Major mines near Kimberley, South Africa (1871–2005), and in Kimberley, NW Australia. Diamond is the hardest natural substance known, and is the most precious of gemstones. Diamonds may be clear and transparent or of many hues, including yellow, green, and blue, depending on the presence of trace amounts of impurities. Black diamonds, generally of poorer quality, are used for industrial purposes.

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For other uses, including the shape ?, see Diamond (disambiguation).

Diamond is the hardest known natural material and one of the two best known forms (or allotropes) of carbon, whose hardness and high dispersion of light make it useful for industrial applications and jewelry. (The other equally well known allotrope is graphite.) Diamonds are specifically renowned as a mineral with superlative physical qualities ? they make excellent abrasives because they can be scratched only by other diamonds, Borazon, ultrahard fullerite, or aggregated diamond nanorods, which also means they hold a polish extremely well and retain luster. About 130 million carats (26,000 kg) are mined annually, with a total value of nearly USD $9 billion. They have been treasured as gemstones since their use as religious icons in India at least 2,500 years ago—and usage in drill bits and engraving tools also dates to early human history. Although synthetic diamonds are produced each year at nearly four times the rate of natural diamonds, the vast majority of synthetic diamonds produced are small imperfect diamonds suitable only for industrial-grade use.

Roughly 49% of diamonds originate from central and southern Africa, although significant sources of the mineral have been discovered in Canada, India, Russia, Brazil, and Australia. The mining and distribution of natural diamonds are subjects of frequent controversy—such as with concerns over the sale of conflict diamonds by African paramilitary groups. There are also allegations that the De Beers Group misuses its dominance in the industry to control supply and manipulate price via monopolistic practices, although in recent years the company's market share has dropped to below 60%.

Material properties

A diamond is a transparent crystal of tetrahedrally bonded carbon atoms. Most notable are its extreme hardness of diamond, its high dispersion index, and high thermal conductivity.

Mechanical properties

Crystal structure

Diamonds typically crystallize in the face-centered cubic crystal system (space group Fdbar{3}m) and consist of tetrahedrally bonded carbon atoms. Diamond's density is 3.52 g·cm⁻³.

The tetrahedral arrangement of atoms is the source of many of diamond?s properties. Other elements of the carbon group such as silicon crystalize like diamond.

Lonsdaleite is a polymorph of diamond (and a distinct mineral species) that crystallizes with hexagonal symmetry. A cryptocrystalline variety of diamond is called carbonado.

Hardness

Diamond is the hardest natural material known, scoring 10 on the relative Mohs scale of mineral hardness and having an absolute hardness value of between 90, 167, and 231 gigapascals in various tests. However, aggregated diamond nanorods, an allotrope of carbon first synthesized in 2005, are now believed to be even harder than diamond.

The hardest diamonds in the world are from the New England area in New South Wales, Australia. These diamonds are generally small, perfect to semiperfect octahedra, and are used to polish other diamonds. As the hardest known naturally occurring material, diamond can be used to polish, cut, or wear away any material, including other diamonds. Common industrial adaptations of this ability include diamond-tipped drill bits and saws, or use of diamond powder as an abrasive. Other specialized applications also exist or are being developed, including use as semiconductors: some blue diamonds are natural semiconductors, in contrast to most other diamonds, which are excellent electrical insulators. Industrial applications, especially as drill bits and engraving tools, also date to ancient times.

The hardness of diamonds also contributes to its suitability as a gemstone. Colored diamonds contain impurities or structural defects that cause the coloration, while pure or nearly pure diamonds are transparent and colorless.

Thermodynamic stability

Like other forms of carbon like coal, diamonds will burn at approximately 800 degrees Celsius, providing that enough oxygen is available. The diamond phase of carbon is metastable with respect to the graphitic phase under normal conditions;

Electromagnetic properties

Optical properties

Diamonds exhibit a high dispersion of visible light. This strong ability to split white light into its component colors is an important aspect of diamond's attraction as a gemstone, giving it impressive prismatic action that results in so-called fire in a well-cut stone. The luster of a diamond, its adamantine brilliance, is a consequence of its high refractive index of 2.417 (at 589.3 nm), which allows total internal reflection to occur easily.

Some diamonds exhibit fluorescence of various colors (predominately blue) under long wave ultraviolet radiation. Most diamonds show no fluorescence although colored diamonds show a wider range of fluorescence than the blue fluorescence normally observed in clear diamonds. Most natural blue diamonds contain boron atoms which replace carbon atoms in the crystal matrix, and also have high thermal conductivity. Specially purified synthetic diamond has the highest thermal conductivity (2000–2500 W/(m·K), five times more than copper) of any known solid at room temperature.

Media

Natural history

Formation

Diamonds are formed by prolonged exposure of carbon bearing materials to high pressure and temperature. On Earth, the formation of diamonds is possible because there are regions deep within the Earth that are at a high enough pressure and temperature that the formation of diamonds is thermodynamically favorable. Under continental crust, diamonds form starting at depths of about 150 kilometers (90 miles), where pressure is roughly 5 gigapascals and the temperature is around 1200 degrees Celsius (2200 degrees Fahrenheit). Diamond formation under oceanic crust takes place at greater depths because of higher temperatures, which require higher pressure for diamond formation. Long periods of exposure to these high pressures and temperatures allow diamond crystals to grow larger.

Through studies of carbon isotope ratios (similar to the methodology used in carbon dating, except with the stable isotopes C-12 and C-13), it has been shown that the carbon found in diamonds comes from both inorganic and organic sources. Some diamonds, known as harzburgitic, are formed from inorganic carbon originally found deep in the Earth's mantle. In contrast, eclogitic diamonds contain organic carbon from organic detritus that has been pushed down from the surface of the Earth's crust through subduction (see plate tectonics) before transforming into diamond. Diamonds that have come to the Earth's surface are generally very old, ranging from under 1 billion to 3.3 billion years old.

Diamonds occur most often as euhedral or rounded octahedra and twinned octahedra known as macles or maccles. As diamond's crystal structure has a cubic arrangement of the atoms, they have many facets that belong to a cube, octahedron, rhombicosidodecahedron, tetrakis hexahedron or disdyakis dodecahedron. Very small diamonds, known as microdiamonds or nanodiamonds, have been found in impact craters where meteors strike the Earth and create shock zones of high pressure and temperature where diamond formation can occur. The magma for such a volcano must originate at a depth where diamonds can be formed, 90 miles (150 km) deep or more (three times or more the depth of source magma for most volcanoes); Not all pipes contain diamonds, and even fewer contain enough diamonds to make mining economically viable.

The magma in volcanic pipes is usually one of two characteristic types, which cool into igneous rock known as either kimberlite or lamproite. These rocks are characteristically rich in magnesium-bearing olivine, pyroxene, and amphibole minerals which are often altered to serpentine by heat and fluids during and after eruption. The most common indicator minerals are chromian garnets (usually bright red Cr-pyrope, and occasionally green ugrandite-series garnets), eclogitic garnets, orange Ti-pyrope, red high-Cr spinels, dark chromite, bright green Cr-diopside, glassy green olivine, black picroilmenite, and magnetite. Kimberlite deposits are known as blue ground for the deeper serpentinized part of the deposits, or as yellow ground for the near surface smectite clay and carbonate weathered and oxidized portion.

Once diamonds have been transported to the surface by magma in a volcanic pipe, they may erode out and be distributed over a large area. A volcanic pipe containing diamonds is known as a primary source of diamonds. Secondary sources of diamonds include all areas where a significant number of diamonds, eroded out of their kimberlite or lamproite matrix, accumulate because of water or wind action. These include alluvial deposits and deposits along existing and ancient shorelines, where loose diamonds tend to accumulate because of their approximate size and density. Diamonds have also rarely been found in deposits left behind by glaciers (notably in Wisconsin and Indiana); however, in contrast to alluvial deposits, glacial deposits are not known to be of significant concentration and are therefore not viable commercial sources of diamond.

Diamonds can also be brought to the surface through certain processes which may occur when two continental plates collide and deeply formed rock is thrust to the surface, although this phenomenon is less understood and currently assumed to be uncommon.

Gemological characteristics

The use of diamonds as gemstones of decorative value is the most familiar use to most people today, and is also the earliest use, with decorative use of diamonds stretching back into antiquity. Four characteristics, known informally as the four Cs, are now commonly used as the basic descriptors of diamonds: these are carat, clarity, color, and cut.

Most gem diamonds are traded on the wholesale market based on single values for each of the four Cs; Consumers who purchase individual diamonds are often advised to use the four Cs to pick the diamond that is "right" for them; These characteristics include physical characteristics such as the presence of fluorescence, as well as data on a diamond's history including its source and which gemological institute performed evaluation services on the diamond. Cleanliness also dramatically affects a diamond's beauty.

There are four major gemological associations which "certify" diamonds: that is, define the four Cs of a diamond.

• Gemological Institute of America (GIA) was the first laboratory to issue modern diamond reports, and holds the highest reputation amongst gemologists for its consistent, conservative grading.
  
• American Gemological Society (AGS) is not as widely recognized nor as old as the GIA, but garners an equally high reputation.
  
• International Gemological Laboratory (IGL) is a generally respected laboratory but suffers from a negative industry reputation for its grading practices, which are perceived by critics as being either less conservative or less consistent than the GIA and AGS.
  
• European Gemological Laboratory USA (EGLUSA) Good reputation among the trade for consistent and fair grading. All else being equal, the value of a diamond increases exponentially in relation to carat weight, since larger diamonds are both rarer and more desirable for use as gemstones. A review of comparable diamonds available for purchase in September 2005 demonstrates this effect (approximate prices for round cut, G color, VS2 diamonds with "1A" cut grade, as listed on www.pricescope.com):
  
  

  Carat size	Cost per carat (US$)	Total cost (US$)
  0.5 carat (50 points)	3,000	1,500
  1.0 carat	6,500	6,500
  1.5 carats	8,500	12,750
  2.0 carats	13,000	26,000
  3.0 carats	17,000	51,000
  5.0 carats	23,000	115,000

  
  
  The price per carat does not increase smoothly with increasing size. As an example, a 0.95 carat diamond may have a significantly lower price per carat than a comparable 1.05 carat diamond, because of differences in demand.
  
  A weekly diamond price list, the Rapaport Diamond Report www.rapaportdiamondreport.com/, is published by Martin Rapaport, CEO of Rapaport Group of New York, for different diamond cuts, clarity and weights. Jewelers often trade diamonds at negotiated discounts off the Rapaport price (e.g., "R -3%").
  
  In the wholesale trade of gem diamonds, carat is often used in denominating lots of diamonds for sale. For example, a buyer may place an order for 100 carats of 0.5 carat, D–F, VS2-SI1, excellent cut diamonds, indicating he wishes to purchase 200 diamonds (100 carats total mass) of those approximate characteristics. Because of this, diamond prices (particularly among wholesalers and other industry professionals) are often quoted per carat, rather than per stone.
  
  Total carat weight (t.c.w.) is a phrase used to describe the total mass of diamonds or other gemstone in a piece of jewelry, when more than one gemstone is used. when placed for sale, indicating the mass of the diamonds in both earrings and not each individual diamond. The Gemological Institute of America (GIA) and others have developed systems to grade clarity, which are generally based on those inclusions which are visible to a trained professional when a diamond is viewed from above, under 10x magnification.
  
  Diamonds become increasingly rare when considering higher clarity gradings. Only about 20 percent of all diamonds mined have a clarity rating high enough for the diamond to be considered appropriate for use as a gemstone; Large cracks close to or breaking the surface may reduce a diamond's resistance to fracture.
  
  Diamonds are graded by the major societies on a scale ranging from flawless to imperfect.

  Color

  
  A chemically pure and structurally perfect diamond is perfectly transparent with no hue, or color. The color of a diamond may be affected by chemical impurities and/or structural defects in the crystal lattice. Depending on the hue and intensity of a diamond's coloration, a diamond's color can either detract from or enhance its value. For example, most white diamonds are discounted in price as more yellow hue is detectable, while intense pink or blue diamonds (such as the Hope Diamond) can be dramatically more valuable.
  
  Most diamonds used as gemstones are basically transparent with little tint, or white diamonds. The most common impurity, nitrogen, replaces a small proportion of carbon atoms in a diamond's structure and causes a yellowish to brownish tint. The system uses a benchmark set of either natural diamonds of known color grade, or precision-crafted cubic zirconia; Diamonds with unusual or intense coloration are sometimes labeled "fancy" by the diamond industry. Gemologists have developed rating systems for fancy colored diamonds, but they are not in common use because of the relative rarity of colored diamonds.

  Cut

  
  Diamond cutting is the art and science of creating a gem-quality diamond out of mined rough. The cut of a diamond describes the manner in which a diamond has been shaped and polished from its beginning form as a rough stone to its final gem proportions. The cut of a diamond describes the quality of workmanship and the angles to which a diamond is cut. Round brilliant diamonds, the most common, are guided by these specific guidelines, though fancy cut stones are not able to be as accurately guided by mathematical specifics.
  
  The techniques for cutting diamonds have been developed over hundreds of years, with perhaps the greatest achievements made in 1919 by mathematician and gem enthusiast Marcel Tolkowsky. He developed the round brilliant cut by calculating the ideal shape to return and scatter light when a diamond is viewed from above. Neither of these tactics make the diamond appear any bigger, and they greatly reduce the sparkle of the diamond. So a poorly cut 1.0 carat diamond may have the same diameter and appear as large as a 0.85 carat diamond. Mathematically, the diameter in millimeters of a round brilliant should approximately equal 6.5 times the cube root of carat weight, or 11.1 times the cube root of gram weight.
  

  Shape

  Diamonds do not show all of their beauty as rough stones;
  
  Diamonds which are not cut to the specifications of Tolkowsky's round brilliant shape (or subsequent variations) are known as "fancy cuts." Cuts are influenced heavily by fashion: the baguette cut—which accentuates a diamond's luster and downplays its fire—was all the rage during the Art Deco period, whereas the princess cut—which accentuates a diamond's fire rather than its luster—is currently gaining popularity.

  Quality

  The quality of a diamond's cut is widely considered the most important of the four Cs in determining the beauty of a diamond; The skill with which a diamond is cut determines its ability to reflect and refract light.
  
  In addition to carrying the most importance to a diamond's quality as a gemstone, the cut is also the most difficult to quantitatively judge. A number of factors, including proportion, symmetry, and the relative angles of various facets, are determined by the quality of the cut and can affect the performance of a diamond. When a diamond is cut for too much "fire," it looks like a cubic zirconia, which gives off much more "fire" than real diamond. An inferior cut will produce a stone that appears dark at the center and in some extreme cases the ring settings may show through the top of the diamond as shadows.
  
  Several different theories on the "ideal" proportions of a diamond have been and continue to be advocated by professional gemologists. SymmetriScope or IdealScope (tests for light leakage, light return and proportions), Hearts and Arrows Viewer (test for "hearts and arrows" characteristic pattern observable on stones exhibiting high symmetry), GemEx BrillianceScope (tests for direct light performance results of a diamond), Isee2 Beauty Evaluator (tests for diffused light performance results for round or octagonal diamonds), and ASET (test for AGS cut grade). Oddly shaped crystals such as macles are more likely to be cut in a fancy cut—that is, a cut other than the round brilliant—which the particular crystal shape lends itself to.
  
  Even with modern techniques, the cutting and polishing of a diamond crystal always results in a dramatic loss of weight; Since the per carat price of diamond shifts around key milestones (such as 1.00 carat), many one-carat diamonds are the result of compromising "Cut" for "Carat." Some jewelry experts advise consumers to buy a 0.99 carat diamond for its better price or buy a 1.10 carat diamond for its better cut, avoiding a 1.00 carat diamond which is more likely to be a poorly cut stone. The movement to understand and measure the light dynamics and behavior of a diamond is historic and probably the most significant event in modern diamond history that will affect how a diamond should be cut to maximize beauty.

  Light Performance

  Light performance deals with how much light, what kind of light and the origin of light being emitted or reflected by a diamond when subject to a light source.
  
  Performance has often been associated with cars, stereos, boats, watches, and computers, but rarely been it ever been used to describe a diamond. A clean diamond is more brilliant and fiery than the same diamond when it is "dirty." Water, dirt, or grease on the bottom of a diamond interferes with the diamond's brilliance and fire. Current practice is to thoroughly clean a diamond before grading its color.
  
  Maintaining a clean diamond can sometimes be difficult, as jewelry settings can obstruct cleaning efforts, and oils, grease, and other hydrophobic materials adhere well to a diamond's surface. ultrasonic cleaners are also popular.
  
  Cleanliness does not affect the diamond's market value, as any competent jeweler will clean the diamond before offering it for sale. However, cleanliness might reflect a diamond's sentimental value: some jewelers have noted a correlation between ring cleanliness and marriage quality www.diamondcuttersintl.com/diamond_education/articles/customers/getting_in_shape.html.

  History

  Diamonds are thought to have been first recognized and mined in India, where significant alluvial deposits of the stone could then be found. The earliest written reference can be found in the Buddhist text, the Anguttara Nikaya another sanskrit text, the Arthashastra, which was completed around 296 BCE and describes diamond's hardness, luster, and dispersion. Diamonds quickly became associated with divinity, being used to decorate religious icons, and were believed to bring good fortune to those who carried them. Ownership was restricted among various castes by color, with only kings being allowed to own all colors of diamond.
  
  In February 2005, a joint Chinese-U.S. team of archaeologists reported the discovery of four corundum-rich stone ceremonial burial axes originating from China's Liangzhu and Sanxingcun cultures (4000 BCE–2500 BCE) which, because of the axes' specular surfaces, the scientists believe were polished using diamond powder news.bbc.co.uk/2/hi/science/nature/4555235.stm www.chinadaily.com.cn/english/doc/2005-02/18/content_417247.htm. Although there are diamond deposits now known to exist close to the burial sites, no direct evidence of coeval diamond mining has been found: the researchers came to this conclusion by polishing corundum using various lapidary abrasives and modern techniques then comparing the results using an atomic force microscope. In his work Naturalis Historia, the Roman writer Pliny the Elder noted diamond's ornamental uses, as well as its usefulness to engravers because of its hardness. Archaeological evidence from Yemen suggests that diamonds were used as drill tips as early as the 4th century BCE. In Europe, however, diamonds disappeared for almost 1,000 years following the rise of Christianity because of two effects: early Christians rejected diamonds because of their earlier use in amulets, and Arabic traders restricted the flow of trade between Europe and India.
  
  Until the late Middle Ages, diamonds were most prized in their natural octahedral state, perhaps with the crystal surfaces polished to increase luster and remove foreign material. Around 1300, the flow of diamonds into Europe increased via Venice's trade network, with most flowing through the low country ports of Bruges, Antwerp, and Amsterdam. During this time, the taboo against cutting diamonds into gem shapes, which was established over 1,000 years earlier in the traditions of India, ended allowing the development of diamond cutting technology to begin in earnest. Over the following centuries, various diamond cuts were introduced which increasingly demonstrated the fire and brilliance that makes diamonds treasured today: the table cut, the briolette (around 1476), the rose cut (mid-16th century), and by the mid-17th century, the Mazarin, the first brilliant cut diamond design. however, diamond cuts have continued to be refined.
  
  The rise in popularity of diamonds as gems seems to have paralleled increasing availability through European history. However, within a century diamonds were popular gems among the moneyed aristocratic and merchant classes, and by at latest 1477 had begun to be used in wedding rings. A number of large diamonds have become historically significant objects, as their inclusion in various sets of crown jewels and the purchase, sale, and sometimes theft of notable diamonds, have sometimes become politicized.

  Record-holding diamonds

  The Cullinan Diamond, part of the British crown jewels, was the largest gem-quality rough diamond ever found (1905), at 3,106.75 carats. One of the diamonds cut from it, Cullinan I or the Great Star of Africa, was formerly the largest gem-quality cut diamond at 530.2 carats, but now that title has been taken by the Golden Jubilee (1985), a 545.67 carat, yellow-brown diamond. The largest flawless and colorless (grade D) diamond is the Centenary Diamond which weighs 273.85 carats. The Millennium Star is the second largest (1990) at 203.04 carats.
  
  

  See also: List of famous diamonds
  

  The diamond industry

  The diamond industry can be broadly separated into two basically distinct categories: one dealing with gem-grade diamonds and another for industrial-grade diamonds.

  Gem diamond industry

  A large trade in gem-grade diamonds exists. Unlike precious metals such as gold or platinum, gem diamonds do not trade as a commodity: there is a substantial mark-up in the sale of diamonds, and there is not a very active market for resale of diamonds. One hallmark of the trade in gem-quality diamonds is its remarkable concentration: wholesale trade and diamond cutting is limited to a few locations (most importantly New York, Antwerp, London, Tel Aviv, Amsterdam and Surat), and a single company—De Beers—controls a significant proportion of the trade in diamonds. They are based in Johannesburg, South Africa and London, England.
  
  The production and distribution of diamonds is largely consolidated in the hands of a few key players, and concentrated in traditional diamond trading centers (the most important being Antwerp). De Beers owns or controls a significant portion of the world's rough diamond production facilities (mines) and distribution channels for gem-quality diamonds. At one time it was thought over 80 percent of the world's rough diamonds passed through the Diamond Trading Company (DTC, a subsidiary of De Beers) in London, but presently the figure is estimated at less than 50 percent. De Beers used its monopoly position to establish strict price controls, and market diamonds directly to consumers in world markets.
  
  The De Beers diamond advertising campaign is acknowledged as one of the most successful and innovative ones in history. Ayer & Son, the advertising firm retained by De Beers in the mid-20th century, succeeded in reviving the American diamond market and opened up new markets, even in countries where no diamond tradition had existed before. Ayer's multifaceted marketing campaign included product placement, advertising the diamond itself rather than the De Beers brand, and building associations with celebrities and royalty.

  Industrial diamond industry

  The market for industrial-grade diamonds operates much differently from its gem-grade counterpart. Industrial diamonds are valued mostly for their hardness and heat conductivity, making many of the gemological characteristics of diamond, including clarity and color, mostly irrelevant. In addition to mined diamonds, synthetic diamonds found industrial applications almost immediately after their invention in the 1950s; another 400 million carats (80,000 kg) of synthetic diamonds are produced annually for industrial use—nearly four times the mass of natural diamonds mined over the same period. Most uses of diamonds in these technologies do not require large diamonds; Specialized applications include use in laboratories as containment for high pressure experiments (see diamond anvil), high-performance bearings, and limited use in specialized windows.
  
  With the continuing advances being made in the production of synthetic diamond, future applications are beginning to become feasible. Garnering much excitement is the possible use of diamond as a semiconductor suitable to build microchips from, or the use of diamond as a heat sink in electronics. Significant research efforts in Japan, Europe, and the United States are under way to capitalize on the potential offered by diamond's unique material properties, combined with increased quality and quantity of supply starting to become available from synthetic diamond manufacturers.

  Diamond Industry organisations

  World Federation of Diamond Bourses (WFDB)
  
  The WFDB was founded in 1947 to unite and to provide bourses trading in rough and polished
  diamonds and precious stones, with a common set of trading practice. The WFDB provides a
  legal framework and convenes to enact regulations for its 25 member diamond bourses.
  
  International Diamond Manufacturers Association (IDMA)
  
  IDMA represents the interests of various manufaturers associations, with respect to current issues concerning the world diamond industry.
  
  World Diamond Council (WDC)
  
  The WDC is a joint committee that was formed by the WFDB and IDMA to ensure the development, implementation and oversight of a tracking system for the export and import of rough diamonds to prevent the exploitation of diamonds for illicit purposes such as war and inhumane acts.
  
  International Diamond Council (IDC)
  
  A joint committee appointed by The World Federation of Diamond Bourses (WFDB) and the International Diamond Manufacturers Association (IDMA) to create an international standard for rules, working methods and nomenclature for diamond grading laboratories. In fact, the amount of power which De Beers has consolidated historically prevented it from direct trade with the United States, as its trade practices led to an indictment for violating antitrust regulations (the case was settled in 2004). The concentration of power only loosens at the retail level, where diamonds are sold by a limited number of distributors, known as sightholders, to jewelers around the world.
  
  

  Sources

  Historically diamonds were known to be found only in alluvial deposits in southern India; While no commercial diamond production exists in the US, Arkansas is the only state to have a verifiable source of diamonds. Today, most commercially viable diamond deposits are in Africa, notably in South Africa, Namibia, Botswana, the Democratic Republic of Congo, Angola, Tanzania and Sierra Leone gnn.tv/videos/2/The_Diamond_Life. There are also commercial deposits being actively mined in the Northwest Territories of Canada, Siberia (mostly in Yakutia territory, for example Mir pipe and Udachnaya pipe), Brazil, and in Northern and Western Australia. Diamond prospectors continue to search the globe for diamond-bearing kimberlite and lamproite pipes.
  
  In some of the more politically unstable central African and west African countries, revolutionary groups have taken control of diamond mines, using proceeds from diamond sales to finance their operations. In response to public concerns that their diamond purchases were contributing to war and human rights abuses in central Africa and west Africa, the diamond industry and diamond-trading nations introduced the Kimberley Process in 2002, which is aimed at ensuring that conflict diamonds do not become intermixed with the diamonds not controlled by such rebel groups. Although the Kimberley Process has been somewhat successful in limiting the number of conflict diamonds entering the market, conflict diamonds smuggled to market continue to persist to some degree (approx. 1% of diamonds traded today are possible conflict diamonds citation needed).
  
  Currently, gem production totals nearly 30 million carats (6,000 kg) of cut and polished stones annually, and over 100 million carats (20,000 kg) of mined diamonds are sold for industrial use each year, as are about 100,000 kg of synthesized diamond.

  Mining

  Only a very small fraction of the diamond ore consists of actual diamonds.

  Distribution

  The Diamond Trading Company, or DTC, is a subsidiary of De Beers and markets rough diamonds produced both by De Beers mines and other mines from which it purchases rough diamond production. DTC performs sophisticated sorting of rough diamonds into over 16,000 categories, and then sells bulk lots of rough diamonds to a limited number of sightholders a few times a year.
  
  Once purchased by sightholders, diamonds are cut and polished in preparation for sale as gemstones. Traditional diamond cutting centers are Antwerp, Amsterdam, Johannesburg, New York, and Tel Aviv. Recently, diamond cutting centers have been established in China, India, and Thailand. Cutting centers with lower costs of labor, notably Surat in Gujarat, India, handle a larger number of smaller carat diamonds, while smaller quantities of larger or more valuable diamonds are more likely to be handled in Europe or North America. The recent expansion of this industry in India, employing low cost labor, has allowed smaller diamonds to be prepared as gems than was previously economically feasible.
  
  Diamonds which have been prepared as gemstones are sold on diamond exchanges called bourses. According to the Rio Tinto Group, in 2002 the diamonds produced and released to the market were valued at US$9 billion as rough diamonds, US$14 billion after being cut and polished, US$28 billion in wholesale diamond jewelry, and retail sales of US$57 billion. www.riotintodiamonds.com/market/industry.asp

  Synthetics, simulants, and enhancements

  
  It is important to distinguish that a synthetic diamond is a true diamond created by a technological process, whereas a diamond simulant is defined as a non-diamond material that is used to simulate the appearance of a true diamond.
  
  The gemological and industrial uses of diamond have created a large demand for raw stones. A portion of this demand is now being met by synthetic diamonds, artificially-made diamonds which have similar properties to natural diamonds. This process has historically produced industrial-grade diamonds, but synthetic diamond producers have recently begun to produce diamonds with high enough quality to penetrate the gem diamond market. Diamonds have been manufactured synthetically for over fifty years.
  
  A diamond's gem quality, which is not as dependent on material properties as industrial applications, has invited both imitation and the invention of procedures to enhance the gemological properties of natural diamonds. Materials which have similar gemological characteristics to diamond but are not real mined or synthetic diamond are known as diamond simulants. Diamond enhancements are specific treatments, performed on natural diamonds (usually those already cut and polished into a gem), which are designed to better the gemological characteristics of the stone in one or more ways. These include laser drilling to remove inclusions, application of sealants to fill cracks, treatments to improve a white diamond's color grade, and treatments to give fancy color to a white diamond.
  
  Currently, trained gemologists with appropriate equipment are able to distinguish natural diamonds from all synthetic and simulant diamonds, and identify all enhanced natural diamonds. The established natural diamond industry has a vested interest in maintaining the distinction between natural diamonds and other diamonds, and has made significant investments toward that end. However, as manufacturing technology improves, synthetic diamonds may become indistinguishable from natural diamonds, and new techniques for creating and treating simulants (such as coating them with a very thin diamond-like layer of carbon) are making it increasingly difficult to distinguish simulants from real diamonds. The point at which diamonds began to be associated with divinity is not known, but early texts indicate that it was recognized in India since at least 400 BCE. Many long dead cultures have sought to explain diamond's superlative properties through divine or mystical affiliations.
  
  In Tibetan Buddhism, also known as Vajrayana (Diamond Vehicle), diamonds are an important symbol, and the Diamond Sutra is one of the most popular texts.
  
  In Western culture, diamonds are the traditional emblem of fearlessness and virtue, but have also often associated with power, wealth, crime and misfortune. Today, diamonds are used to symbolize eternity and love, being often seen adorning engagement rings and sometimes wedding rings as well. The first diamond engagement ring can be traced to the marriage of Maximilian I (then Archduke of Austria) to Mary of Burgundy in 1477. Inaccessibility of diamonds to the vast majority of the population limited the popularity of diamonds as betrothal jewels during this period.
  
  The LifeGem company further taps modern symbolism by purporting to synthetically convert the carbonized remains of people or pets into "memorial diamonds." However, many people feel very uncomfortable at the thought of wearing the carbonized remains of people as jewelry.
  
  The diamond is the birthstone for people born in the month of April, and is also used as the symbol of a sixty-year anniversary, such as a Diamond Jubilee (see hierarchy of precious substances).
  
  Diamonds are a common focus of fiction. Scott Fitzgerald's "The Diamond as Big As the Ritz" (1922), and Neal Stephenson's The Diamond Age (1995).

  Symbolism in the Occult

  Historically, and in occultist myths, it has been claimed that diamonds possess several supernatural powers:
  
  • A diamond gives victory to he who carries it bound on his left arm, no matter the number of enemies.
    
  • Panics, Pestilences, enchantments, all fly before it; hence, it is good for sleepwalkers and the insane.
    
  • It deprives lodestone and magnets of their virtue (i.e., ability to attract iron).Pliny the Elder, The Natural History (trans. 15.
    
  • Arabic diamonds are said to attract iron greater than a magnet.
    
  • A diamond's hardiness can only be broken by smearing it with fresh goat's blood.
    

  References

  
  
  
  
  
  
  

  • American Museum of Natural History. "The New Diamond Age". "THE DIAMOND INVENTION" (Complete book, includes "Chapter 20: Have you ever tried to sell a diamond?")
    
  • Eppler, W.F. & Ridd, M., (1990) Nitrogen defect aggregation of some Australasian diamonds: Time-temperature constraints on the source regions of pipe and alluvial diamonds. Retrieved Oct 21,2005.
    
  • Supercomputing Institute.of diamond growth".Retrieved Nov 01,2005.
    
  • Carnegie Institution."Very Large Diamonds Produced Very Fast".Retrieved Nov 01,2005.
    
  • Spence, Lewis. "A guide to diamond industry organisations".