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DIAMONDS ARE SHINY. ha ha ha !
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{{otheruses4|the mineral|the gemstone|Diamond (gemstone)|other uses, including the shape <big>]</big>}}
{{Infobox mineral
| name = Diamond
| category = Native Minerals
| boxwidth =
| boxbgcolor =
| image = Brillanten.jpg
| imagesize = 300 <!-- this value is in px -->
| caption = A scattering of round-brilliant cut diamonds shows off the many reflecting facets.
| formula = C
| molweight = 12.01 u
| color = Typically yellow, brown or gray to colorless. Less often in blue, green, black, translucent white, pink, violet, orange, purple and red.<ref name="GRG"/>
| habit = ]
| system = Isometric-Hexoctahedral (Cubic)
| twinning =
| cleavage = 111 (perfect in four directions)
| fracture = ] - step like
| tenacity =
| mohs = 10<ref name="GRG"/>
| luster = ]<ref name="GRG"/>
| polish = ]<ref name="GRG">], ''GIA Gem Reference Guide'' 1995, ISBN 0-87311-019-6</ref>
| refractive = 2.4175–2.4178
| opticalprop = Singly Refractive<ref name="GRG"/>
| birefringence = none<ref name="GRG"/>
| dispersion = .044<ref name="GRG"/>
| pleochroism = none<ref name="GRG"/>
| fluorescence= colorless to yellowish stones - inert to strong in long wave, and typically blue. Weaker in short wave.<ref name="GRG"/>
| absorption = In pale yellow stones a 415.5 nm line is typical. Irradiated and annealed diamonds often show a line around 594 nm when cooled to low temperatures.<ref name="GRG"/>
| streak = White
| gravity = 3.52 (+/- .01)<ref name="GRG"/>
| density = 3.5-3.53 g/cm³
| melt =
| fusibility =
| diagnostic =
| solubility =
| diaphaneity = Transparent to subtransparent to translucent
| other =
}}


REBELS WERE HERE
<!--First paragraph Chemistry and Material Properties, Industry Size-->
In ], '''diamond''' is the ] where the carbon atoms are arranged in an isometric-hexoctahedral crystal lattice. Its hardness and high ] of ] make it useful for industrial applications and ]. It is the ] known ] and the fifth-hardest{{Fact|date=April 2008}} known ] after ], ], and ].

Diamonds are specifically renowned as a material with superlative physical qualities; they make excellent ]s because they can be scratched only by other diamonds, ], ultrahard fullerite, rhenium diboride, or aggregated diamond ], which also means they hold a polish extremely well and retain their ]. Approximately 130 million ] (26,000 kg) are mined annually, with a total value of nearly ]9 ], and about {{convert|100000|kg|abbr=on}} are synthesized annually.<ref>{{cite journal|last = Yarnell|first=Amanda|title=The Many Facets of Man-Made Diamonds|journal=Chemical and Engineering News|volume=82|issue=5|pages=26–31|publisher=American Chemical Society|date=2004|url=http://pubs.acs.org/cen/coverstory/8205/8205diamonds.html|id =ISSN 0009-2347|accessdate=2006-10-03 }}</ref>

<!--Second paragraph: Etymology and Applications-->
The name ''diamond'' derives from the ] ''adamas'' (αδάμας; “invincible”). They have been treasured as ]s since their use as ] in ] and usage in ] tools also dates to early ].<ref>{{cite book |title = Natural History: A Selection | author = ] | publisher = Penguin Classics | pages = p. 371 | isbn = 0140444130}}</ref><ref name=ancient_China>{{cite news | url = http://news.bbc.co.uk/2/hi/science/nature/4555235.stm | title = Chinese made first use of diamond | publisher = BBC News | date= 17 May 2005 | accessdate = 2007-03-21}}</ref> Popularity of diamonds has risen since the 19th century because of increased supply, improved cutting and polishing techniques, growth in the world economy, and innovative and successful advertising campaigns. They are commonly judged by the “four Cs”: ''carat'', ''clarity'', ''color'', and ''cut''.

<!--Third paragraph: Mining and Distribution-->
Roughly 49% of diamonds originate from central and southern ], although significant sources of the mineral have been discovered in ], ], ], ], and ]. They are mined from ] and ] ]s, which can bring diamond crystals, originating from deep within the Earth where high pressures and temperatures enable them to form, to the surface. The mining and distribution of natural diamonds are subjects of frequent controversy such as with concerns over the sale of '']s'' (aka ''blood diamonds'') by African ] groups.

==Material properties==
{{main|Material properties of diamond}}
{{seealso|Crystallographic defects in diamond}}
]
A diamond is a ] ] of ] bonded carbon atoms and crystallizes into the ] ] structure. Diamonds have been adapted for many uses because of the material's exceptional physical characteristics. Most notable are its extreme hardness, its high ] index, and extremely high ] (900 – 2320 W/m K), with a ] of 3820 K (3547 °C / 6420 °F) and a ] of 5100 K (4827 °C / 8720 °F).<ref></ref> Naturally occurring diamonds have a density ranging from 3.15 to 3.53 g/cm³, with very pure diamond typically extremely close to 3.52 g/cm³.

====Hardness====
Diamond is the hardest natural material known to humankind; hardness is defined as resistance to scratching.<ref>{{cite web|url= http://www.gemcutters.org/LDA/hardness.htm|date= 1998 |accessdate=2007-08-19 | title= "The Hardness of Minerals and Rocks" by William S. Cordua|work= Lapidary Digest}} Hosted at </ref> Diamond has a hardness of 10 (hardest) on ].<ref name="AMNH">American Museum of Natural History> Retrieved March 9, 2005</ref> Diamond's hardness has been known since antiquity, and is the source of its name.

The hardest diamonds in the world are from the ] area in ], ]. These diamonds are generally small, perfect to semiperfect octahedra, and are used to polish other diamonds. Their hardness is considered to be a product of the ] form, which is single stage growth crystal. Most other diamonds show more evidence of multiple growth stages, which produce inclusions, flaws, and defect planes in the crystal lattice, all of which affect their hardness.<ref name="Taylor">{{cite journal | author = Taylor, W.R., Lynton A.J. & Ridd, M. | year = 1990| url = http://www.minsocam.org/ammin/AM75/AM75_1290.pdf | title = Nitrogen defect aggregation of some Australasian diamonds: Time-temperature constraints on the source regions of pipe and alluvial diamonds | format = PDF | journal = American Mineralogist | volume = 75 | pages =pp. 1290–1310}}</ref>

The hardness of diamonds contributes to its suitability as a ]. Because it can only be scratched by other diamonds, it maintains its polish extremely well. Unlike many other gems, it is well-suited to daily wear because of its resistance to scratching&mdash;perhaps contributing to its popularity as the preferred gem in an ] or ], which are often worn every day.

Industrial use of diamonds has historically been associated with their hardness; this property makes diamond the ideal material for cutting and grinding tools. As the hardest known naturally-occurring material, diamond can be used to polish, cut, or wear away any material, including other diamonds. However, diamond is a poor choice for machining ferrous alloys at high speeds. At the high temperatures created by high speed machining, carbon is soluble in iron, leading to greatly increased wear on diamond tools as compared to other alternatives. Common industrial adaptations of this ability include diamond-tipped ]s and saws, or use of diamond powder as an ]. Industrial-grade diamonds are either unsuitable for use as gems or synthetically produced, which lowers their value and makes their use economically feasible.

====Electrical conductivity====
Other specialized applications also exist or are being developed, including use as ]s: some blue diamonds are natural semiconductors, in contrast to most other diamonds, which are excellent electrical ]s.<ref name="AMNH"/> However, substantial conductivity has been observed for undoped diamond when exposed to air.<ref name="Landstrass">{{cite journal | author = Landstrass, M.I., Ravi, K.V. | year = 1989| journal = Applied Physics Letters | volume = 55 | pages =p. 975}}</ref>

====Toughness====
Toughness relates to a material's ability to resist breakage from forceful impact. The ] of natural diamond has been measured as 3.4 MN m<sup>-3/2</sup>,<ref>{{cite journal| last = Field| first=J E| title=Strength and Fracture Properties of Diamond| journal=Philosophical Magazine A| volume=43 |issue=3| pages=595–618 |publisher=Taylor and Francis Ltd|date=1981| accessdate = 2006-02-11 }}</ref> which is good compared to other gemstones, but poor compared to most engineering materials. As with any material, the macroscopic geometry of a diamond contributes to its resistance to breakage. Diamond is therefore more fragile in some orientations than others.

====Color====
{{main|Diamond color}}
Diamond color can occur in blue, green, black, translucent white, pink, violet, orange, purple and red, though yellow and brown are by far the most common colors.<ref name="AMNH"/> "Black" diamonds are not truly black, but rather contain numerous dark inclusions that give the gems their dark appearance. Colored diamonds contain impurities or structural defects that cause the coloration, while pure or nearly pure diamonds are transparent and colorless. Most diamond impurities replace a carbon atom in the ], known as a ]. The most common impurity, ], causes a slight to intense yellow coloration depending upon the type and concentration of nitrogen present.<ref name="AMNH"/> The ] (GIA) classifies low saturation yellow and brown diamonds as diamonds in the ''normal color range'', and applies a grading scale from 'D' (colorless) to 'Z' (light yellow).

In October 2007 a blue diamond fetched nearly $8 million. The blue hue was a result of trace amounts of boron in the stone's crystal structure.<ref>, YAHOO! News</ref>

====Identification====
Diamonds can be identified via their high thermal conductivity. Their high ] is also indicative, but other materials have similar refractivity. Diamonds do cut glass, but other materials above glass on ] such as quartz do also. Diamonds easily scratch other diamonds, but this damages both diamonds.<ref></ref>

==Natural history==
===Formation===
The formation of natural diamond requires very specific conditions. Diamond formation requires exposure of carbon-bearing materials to high ], ranging approximately between ] ]s,<ref name="GIAGrading4">''Diamonds and Diamond Grading: Lesson 4 How Diamonds Form.'' Gemological Institute of America,, Carlsbad, California., 2002</ref> but at a comparatively low ] range between approximately 1652–2372 °F (900–1300 °C).<ref name="GIAGrading4"/> These conditions are known to be met in two places on Earth; in the ] below relatively stable ]s, and at the site of a ] strike.

====Diamonds formed in cratons====
The conditions for diamond formation to happen in the lithospheric mantle occur at considerable depth corresponding to the aforementioned requirements of temperature and pressure. These depths are estimated to be in between 140–190 kilometers (90–120 miles)<ref name="GIAGrading4"/><ref name="AMNH"/> though occasionally diamonds have crystallized at depths of 300-400 km (180-250 miles) as well.<ref name=Sevdermish>{{cite book | last = M. Sevdermish and A. Mashiah | title = The Dealer's Book of Gems and Diamonds | publisher = Kal Printing House, Israel | year = 1995}}</ref> The rate at which ] into the Earth varies greatly in different parts of the Earth. In particular, under oceanic plates the temperature rises more quickly with depth, beyond the range required for diamond formation at the depth required.<ref name="GIAGrading4"/> The correct combination of temperature and pressure is only found in the thick, ancient, and stable parts of ]s where regions of lithosphere known as '']s'' exist.<ref name="GIAGrading4"/> Long residence in the cratonic lithosphere allows diamond crystals to grow larger.
]

Through studies of carbon ] ratios (similar to the methodology used in ], except with the ]s 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 ], are formed from inorganic carbon originally found deep in the Earth's ]. In contrast, ] diamonds contain organic carbon from organic ] that has been pushed down from the surface of the Earth's ] through ] (see ]) before transforming into diamond.<ref name="AMNH"/> These two different source carbons have measurably different <sup>13</sup>C:<sup>12</sup>C ratios. Diamonds that have come to the Earth's surface are generally very old, ranging from under 1 ] to 3.3 billion years old.

Diamonds occur most often as ] or rounded ] and ] octahedra known as ''macles'' or ''maccles''. As diamond's crystal structure has a cubic arrangement of the atoms, they have many ]s that belong to a ], ], ], ] or ]. The crystals can have rounded off and unexpressive edges and can be elongated. Sometimes they are found grown together or form double "twinned" crystals grown together at the surfaces of the octahedron. These different shapes and habits of the diamonds result from differing external circumstances. Diamonds (especially those with rounded crystal faces) are commonly found coated in ''nyf'', an opaque gum-like skin.<ref>Webster, Robert, and Read, Peter G. (Ed.) (2000). ''Gems: Their sources, descriptions and identification'' (5th ed.), p. 17. Butterworth-Heinemann, Great Britain. ISBN 0-7506-1674-1.</ref>

====Diamonds and meteorite impact craters====
Diamonds can also form in other natural high-pressure events. Very small diamonds, known as ''microdiamonds'' or ''nanodiamonds'', have been found in ] ]s. Such ] create shock zones of high pressure and temperature suitable for diamond formation. Impact-type microdiamonds can be used as one indicator of ancient impact craters.<ref name="AMNH" />

====Extraterrestrial diamonds====
Not all diamonds found on earth originated here. A type of diamond called ] diamond that is found in ] and Africa was deposited there via an asteroid impact (not formed from the impact) about 3 billion years ago.<ref name=Garai2006>{{cite journal | author = Garai, J. | coauthors = Haggerty, S.E.; Rekhi, S.; Chance, M. | year = 2006 | title = Infrared Absorption Investigations Confirm the Extraterrestrial Origin of Carbonado Diamonds | journal = The Astrophysical Journal | volume = 653 | issue = 2 | pages = L153-L156 | doi = 10.1086/510451 }}</ref><ref name=Carbonardo>{{cite web | url = http://www.nsf.gov/news/news_summ.jsp?cntn_id=108270&org=NSF | title = Diamonds from Outer Space: Geologists Discover Origin of Earth's Mysterious Black Diamonds | publisher = National Science Foundation | date= 8 January 2007 | accessdate = 2007-10-28}}</ref> These diamonds formed in the intrastellar environment.

] in many meteorites found on earth contain nanodiamonds of extraterrestrial origin, probably formed in ]s.

] ]s have been described as having a carbon core and were hyped in a 2004 news headline as diamond.<ref>{{cite web |url=http://www.theage.com.au/articles/2004/02/17/1076779973101.html |title=Biggest Diamond Out of This World |accessdate=11 November |accessyear=2007 |last=Cauchi |first=Stephen |date=18 February, 2004|year=2004 |month=February}}</ref>

===Surfacing===
]

Diamond-bearing rock is brought close to the surface through deep-origin ] eruptions. The ] for such a volcano must originate at a depth where diamonds can be formed,<ref name="AMNH"/> 150 km (90 miles) deep or more (three times or more the depth of source magma for most volcanoes); this is a relatively rare occurrence. These typically small surface volcanic craters extend downward in formations known as ]s.<ref name="AMNH"/> The pipes contain material that was transported toward the surface by volcanic action, but was not ejected before the volcanic activity ceased. During eruption these pipes are open to the surface, resulting in open circulation; many ]s of surface rock and even wood and/or ]s are found in volcanic pipes. Diamond-bearing volcanic pipes are closely related to the oldest, coolest regions of ] (]s). This is because cratons are very thick, and their ] mantle extends to great enough depth that diamonds are stable. 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 ] known as either ] or ].<ref name="AMNH"/> The magma itself does not contain diamond; instead, it acts as an elevator that carries deep-formed rocks (xenoliths), minerals (]s), and fluids upward. These rocks are characteristically rich in ]-bearing ], ], and ] minerals<ref name="AMNH"/> which are often altered to ] by heat and fluids during and after eruption. Certain ''indicator minerals'' typically occur within diamondiferous kimberlites and are used as mineralogic tracers by prospectors, who follow the indicator trail back to the volcanic pipe which may contain diamonds. These minerals are rich in ] (Cr) or ] (Ti), elements which impart bright colors to the minerals. The most common indicator minerals are chromian ]s (usually bright red Cr-], and occasionally green ugrandite-series garnets), eclogitic garnets, orange Ti-pyrope, red high-Cr ]s, dark ], bright green Cr-], glassy green ], black ], and ].<ref name="AMNH"/> Kimberlite deposits are known as ''blue ground'' for the deeper serpentinized part of the deposits, or as ''yellow ground'' for the near surface ] ] and carbonate ] and ] portion.

Once diamonds have been transported to the surface by magma in a volcanic pipe, they may ] 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 ] 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 ] and ]); however, in contrast to ]s, glacial deposits are not known to be of significant concentration and are therefore not viable commercial sources of diamond.

== History and gemological characteristics ==
{{main|Diamond (gemstone)}}
Diamonds are thought to have been first recognized and mined in ] (] being one of them), where significant alluvial deposits of the stone could then be found along the rivers Penner, Krishna and Godavari. Diamonds have been known in India for at least 3000 years but most likely 6000 years.<ref name=hershey>{{cite book | last = Hershey MS PhD | first = Willard | title = The Book of Diamonds | publisher = Hearthside Press New York | year = 1940}}</ref>
The most familiar usage of diamonds today is as gemstones used for ] a usage which dates back into ]. The ] of white light into ]s, is the primary gemological characteristic of gem diamonds. In the twentieth century, experts in the field of '']'' have developed methods of grading diamonds and other gemstones based on the characteristics most important to their value as a gem. Four characteristics, known informally as the ''four Cs'', are now commonly used as the basic descriptors of diamonds: these are ''carat'', ''cut'', ''color'', and ''clarity''.

==The diamond industry==
{{See also|Diamonds as an investment}}
] diamond set in a ring]]

The diamond industry can be broadly separated into two basically distinct categories: one dealing with gem-grade diamonds and another for industrial-grade diamonds. While a large trade in both types of diamonds exists, the two markets act in dramatically different ways.

===Gem diamond industry===
{{main|Diamond (gemstone)}}

A large trade in ]-grade diamonds exists. Unlike ]s such as ] or ], gem diamonds do not trade as a ]: 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 ] is limited to a few locations. 92% of diamond pieces cut in 2003 were in ], ], India. Other important centers of diamond cutting and trading are ], ], ], ], ]. A single company&mdash;]&mdash;controls a significant proportion of the trade in diamonds. They are based in ], ] and ], ].

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 ], where 80% of all rough diamonds, 50% of all cut diamonds and more than 50% of all rough, cut and industrial diamonds combined are handled.{{Fact|date=November 2007}} This makes Antwerp the de facto 'world diamond capital'. ], however, along with the rest of the United States, is where almost 80% of the world's diamonds are sold, including at auction. Also, the largest and most unusually shaped rough diamonds end up in New York. The De&nbsp;Beers company, as the world's largest diamond miner holds a clearly dominant position in the industry, and has done so since soon after its founding in 1888 by the British imperialist ]. De Beers owns or controls a significant portion of the world's rough diamond production facilities (]) and ] for gem-quality diamonds. The company and its subsidiaries own mines that produce some 40 percent of annual world diamond production. At one time it was thought over 80 percent of the world's rough diamonds passed through the ] (DTC, a subsidiary of De Beers) in London, but presently the figure is estimated at less than 50 percent.

The ] is acknowledged as one of the most successful and innovative campaigns in history. ], 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. N.W. Ayer's multifaceted marketing campaign included ], advertising the diamond itself rather than the De Beers brand, and building associations with celebrities and royalty. This coordinated campaign has lasted decades and continues today; it is perhaps best captured by the ] "a diamond is forever".

Further down the ], members of The ] (WFDB) act as a medium for wholesale diamond exchange, trading both polished and rough diamonds. The WFDB consists of independent diamond bourses in major cutting centres such as Tel Aviv, Antwerp, Johannesburg and other cities across the USA, Europe and Asia.

In 2000, the WFDB and The International Diamond Manufacturers Association established the ] to prevent the trading of diamonds used to fund war and inhumane acts.

WFDB's additional activities also include sponsoring the ] every two years, as well as the establishment of the '']'' (IDC) to oversee diamond grading.

===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. This helps explain why 80% of mined diamonds (equal to about 100 million carats or 20,000 kg annually), unsuitable for use as gemstones and known as '']'', are destined for industrial use. In addition to mined diamonds, ]s found industrial applications almost immediately after their invention in the 1950s; another 3 billion carats (600 ]) of synthetic diamond is produced annually for industrial use.

The dominant industrial use of diamond is in cutting, drilling, grinding, and polishing. Most uses of diamonds in these technologies do not require large diamonds; in fact, most diamonds that are gem-quality except for their small size, can find an industrial use. Diamonds are embedded in drill tips or saw blades, or ground into a powder for use in grinding and polishing applications. Specialized applications include use in laboratories as containment for ] (see ]), high-performance ], and limited use in specialized ]s.

With the continuing advances being made in the production of synthetic diamonds, future applications are beginning to become feasible. Garnering much excitement is the possible use of diamond as a ] suitable to build ]s from, or the use of diamond as a ] in ].

===Diamond supply chain===
{{See also|List of diamond mines}}

The diamond supply chain is controlled by a limited number of powerful businesses, and is also highly concentrated in a small number of locations around the world.

====Mining, sources and production====
Only a very small fraction of the diamond ore consists of actual diamonds. The ore is crushed, during which care has to be taken in order to prevent larger diamonds from being destroyed in this process and subsequently the particles are sorted by density. Today, diamonds are located in the diamond-rich density fraction with the help of ], after which the final sorting steps are done by hand. Before the use of ]s became commonplace, the separation was done with grease belts; diamonds have a stronger tendency to stick to grease than the other minerals in the ore.

Historically diamonds were known to be found only in alluvial deposits in ].<ref name=Catelle1>{{cite book | last = Catelle | first = W.R. | title = The Diamond | publisher = John Lane Company | year = 1911}} Page 159 discussion on Alluvial diamonds in India and elsewhere as well as earliest finds </ref> India led the world in diamond production from the time of their discovery in approximately the 9th century BCE<ref name=Ball>{{cite book | last = Ball | first = V | title = Diamonds, Gold and Coal of India | publisher = London, Truebner & Co. | year = 1881}} Ball was a Geologist in British service. Chapter I, Page 1 </ref><ref name= hershey/> to the mid-18th century AD, but the commercial potential of these sources had been exhausted by the late 18th century and at that time India was eclipsed by Brazil where the first non-Indian diamonds were found in 1725.<ref name = hershey/>

Diamond production of primary deposits (kimberlites and lamproites) only started in the 1870's after the discovery of the Diamond fields in South Africa. Production has increased over time and now an accumulated total of 4.5 billion carats have been mined since that date.<ref name=giasummer2007>{{cite journal| last = Janse | first= A J A | title= Global Rough Diamond Production Since 1870 | journal= Gems and Gemology | volume= XLIII |issue= Summer 2007| pages=98-119 |publisher=GIA date=2007| accessdate = 2007-09-10 }}</ref> Interestingly 20% of that amount has been mined in the last 5 years alone and during the last ten years 9 new mines have started production while 4 more are waiting to be opened soon. Most of these mines are located in Canada, Zimbabwe, Angola, and one in Russia.<ref name = giasummer2007/>

In the ], diamonds have been found in ], ], and ].<ref name=DGemGLorenz>{{cite journal| last = Lorenz| first= V | title=Argyle in Western Australia: The world's richest diamondiferous pipe; its past and future| journal=Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft | volume=56 |issue=1/2| pages=35-40 |publisher=DGemG|date=2007| }}</ref><ref></ref> In 2004, a startling discovery of a microscopic diamond in the ]<ref></ref> led to the January 2008 bulk-sampling of ] in a remote part of ].<ref></ref>

Today, most commercially viable diamond deposits are in ], ], ] and the ].<ref>{{cite web | url = http://gnn.tv/videos/2/The_Diamond_Life | title = The Diamond Life | first = Stephen | last = Marshall |coauthors = Josh Shore | year = 2004 |accessdate = 2007-03-21 }}</ref> In 2005, Russia produced almost one-fifth of the global diamond output, reports the ]. Australia boasts the richest diamondiferous pipe with production reaching peak levels of {{convert|42|MT}} per year in the 1990's.<ref name = DGemGLorenz/>

There are also commercial deposits being actively mined in the ] of ], ] (mostly in ], for example ] and ]), Brazil, and in Northern and Western ]. Diamond prospectors continue to search the globe for diamond-bearing ] and ] pipes.
]

===="Blood" diamonds====
{{main|Blood diamond}}
In some of the more politically unstable central African and west African countries, revolutionary groups have taken control of ], using proceeds from diamond sales to finance their operations. Diamonds sold through this process are known as ''conflict diamonds'' or ''blood diamonds''. Major diamond trading corporations continue to fund and fuel these conflicts by doing business with armed groups. In response to public concerns that their diamond purchases were contributing to war and ] in ] and ], the ], the diamond industry and diamond-trading nations introduced the ] in 2002, which is aimed at ensuring that conflict diamonds do not become intermixed with the diamonds not controlled by such rebel groups, by providing documentation and certification of diamond exports from producing countries to ensure that the proceeds of sale are not being used to fund criminal or revolutionary activities. Although the Kimberley Process has been moderately successful in limiting the number of conflict diamonds entering the market, conflict diamonds smuggled to market continue to persist to some degree (approx. 2–3% of diamonds traded today are possible conflict diamonds<ref>{{cite web | url = http://www.worlddiamondcouncil.com/antwerp.shtml | title = Joint Resolution - World Federation of Diamond Bourses (WFDB) and International Diamond Manufacturers Association | publisher = World Diamond Council | date= July 19, 2000 |accessdate = 2006-11-05 }}</ref>). According to the 2006 book ''The Heartless Stone'', two major flaws still hinder the effectiveness of the Kimberley Process: the relative ease of smuggling diamonds across African borders and giving phony histories, and the violent nature of diamond mining in nations that are not in a technical state of war and whose diamonds are therefore considered "clean."<ref>{{cite book | title = The Heartless Stone: A Journey Through the World of Diamonds, Deceit, and Desire | first = Tom | last = Zoellner | publisher = St. Martin's Press | year = 2006 | isbn = 0312339690 }}</ref>

The Canadian Government has setup a body known as Canadian Diamond Code of Conduct<ref>{{cite web | title = Voluntary Code of Conduct For Authenticating Canadian Diamond Claims | url = http://www.canadiandiamondcodeofconduct.ca/html/Code_EN_Jan_06_FINAL.pdf | publisher = The Canadian Diamond Code Committee | format = PDF | year = 2006 | accessdate = 2007-10-30 }}</ref> to help authenticate Canadian diamonds. This is a very stringent tracking system of diamonds and helps protect the 'conflict free' label of Canadian diamonds.

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.

====Distribution====
The ], 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. Once purchased by sightholders, diamonds are cut and polished in preparation for sale as gemstones. The cutting and polishing of rough diamonds is a specialized skill that is concentrated in a limited number of locations worldwide. Traditional diamond cutting centers are ], ], ], ], and ]. Recently, diamond cutting centers have been established in ], ], and ]. Cutting centers with lower cost of labor, notably ] in ], handle a larger number of smaller carat diamonds, while smaller quantities of larger or more valuable diamonds are more likely to be handled in ] or ]. The recent expansion of this industry in India, employing low cost labor, has allowed smaller diamonds to be prepared as gems in greater quantities than was previously economically feasible.

Diamonds which have been prepared as gemstones are sold on diamond exchanges called ''bourses''. There are 26 registered diamond bourses.<ref>{{cite web | url = http://www.worldfed.com/website/boursedirectory.html | title = Bourse listing | accessdate = 2007-04-04 | work = World Federation of Diamond Bourses}}</ref> This is the final tightly controlled step in the diamond supply chain; wholesalers and even retailers are able to buy relatively small lots of diamonds at the bourses, after which they are prepared for final sale to the consumer. Diamonds can be sold already set in jewelry, or as is increasingly popular, sold unset ("loose"). According to the ], 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 ], and retail sales of US$57 billion.

===Crater of Diamonds State Park===
The ] is an Arkansas State Park located near Murfreesboro in ], USA containing the only diamond bearing site in the world that is open to the public.

==Synthetics, simulants, and enhancements==
{{main|Synthetic diamond|Diamond simulant|Diamond enhancement}}
Natural diamonds have formed naturally within the earth. ]s are purely manufactured. A ] is defined as a non-diamond material that is used to simulate the appearance of a diamond. Diamond-simulant gems are often referred to as ].

The gemological and industrial uses of diamond have created a large demand for rough stones. The demand for industrial diamonds has long been satisfied in large part by ]s, which have been manufactured by various processes for more than half a century. However, in recent years it has become possible to produce gem-quality synthetic diamonds of significant size.<ref name=Growth>{{cite web | publisher = ] | url = http://www.amnh.org/exhibitions/diamonds/growing.html | title = The Nature of Diamonds: 5. Growing Diamonds | accessdate = 2007-03-21}}</ref>

The majority of commercially available synthetic diamonds are yellow in color and produced by so called High Pressure High Temperature (HPHT) processes.<ref>{{cite journal| last = Shigley et al.| first=J E| title=Gemesis Laboratory Created Diamonds| journal=Gems and Gemology| volume=38 |issue=4| pages=301–309 |publisher=GIA |date=2002| accessdate = 2007-05-28 }}</ref> The yellow color is caused by nitrogen impurities. Other colors may also be reproduced such as blue, green or pink which are a result of the addition of boron or from irradiation after synthesis.<ref>{{cite journal| last = Shigley et al.| first=J E| title=Lab Grown Colored Diamonds from Chatham Created Gems | journal=Gems and Gemology| volume=40 |issue=2| pages=128-145|publisher=GIA | date=2004| accessdate = 2007-05-28 }}</ref>

At present the annual production of gem quality synthetic diamonds is only a few thousand carats, whereas the total production of natural diamonds is around 120 million carats. Although the production of colorless synthetic diamonds is dwarfed by that of natural diamonds, one can only find one fancy colored diamond for every 10.000 colorless ones. Since almost the complete production of synthetic diamonds consists of fancy diamonds, there is a high probability that the larger fancy colored diamonds (over 1.5 carats) will be synthetic.<ref name=Donoghue>{{cite book | last = O'Donoghue | first = Michael | title = Gems | publisher = Elsevier | year = 2006}} Page 101, 102</ref>

Today, trained gemologists can generally also distinguish between natural diamonds and synthetic diamonds. Although synthetic and natural diamonds are theoretically identical and indistinguishable from each other, diamonds from each of the two categories usually incorporate their own characteristic imperfections, arising from the circumstances of their creation, that allow them to be distinguished from each other. In the case of synthetic diamonds, for example, depending on the method of production (either high-pressure/high-temperature produced or ] produced) and the color of the diamond (colored, D-Z color range or D-J color range), several methods of identification can be attempted by a gemologist or gemlab: CVD diamonds can usually be identified by an orange fluorescence, D-J colored diamonds can be screened through the Swiss Gemological Organization's (SSEF)<ref>E </ref> Diamond Spotter, and stones in the D-Z color range can be examined through the DiamondSure UV/visible spectrometer which is a tool developed by De Beers.<ref>{{cite journal| last = Welbourn| first=Christopher| title=Identification of Synthetic Diamonds: Present Status and Future Developments/Proceedings of the 4th International Gemological Symposium | journal=Gems and Gemology| volume=42 |issue=3| pages=34-35|publisher=GIA | date=2006| accessdate = 2007-05-28 }}</ref> Similarly, natural diamonds usually have minor imperfections and flaws, such as inclusions of foreign material, that are not seen in synthetic diamonds. The origin of a truly ''perfect'' diamond (natural or synthetic) cannot be determined and is largely moot given that perfect diamonds are currently rare from both sources.

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 mined or synthetic diamond are known as ''diamond simulants''. The most familiar diamond simulant to most consumers is ] (commonly abbreviated as CZ); recently ] has also gained popularity and has often been mischaracterized as a diamond simulant, although it is sold and retailed as a replacement for diamond. Both CZ and moissanite are synthetically produced. However, CZ is a diamond simulant. 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 simulant diamonds, and they can identify all enhanced natural diamonds. Coatings are more and more used to give a diamond simulant such as cubic zirconia a more "diamond-like" appearance. One such substance, which is heavily advertised, is what scientists refer to as "diamond-like carbon". This is an amorphous carbonaceous material that has some physical properties which are similar to that of the diamond. Advertising suggests (rightfully so or not) that such a coating would transfer some of these diamond-like properties to the coated stone, hence enhancing the diamond simulant. However, modern techniques such as ] should easily identify such as treatment.<ref>{{cite journal| last = Shigley | first=J E| title=Observations on new coated gemstones | journal=Gemmologie: Zeitschrift der Deutschen Gemmologischen Gesellschaft | volume=56 |issue=1/2| pages=53-56|publisher=DGemG |date= Juni 2007| accessdate = 2007-08-07 }}</ref>

Producing large synthetic diamonds threatens the business model of the diamond industry, and the ultimate effect of the ready availability of gem-quality diamonds at low cost in the future is hard to predict at this time.

The screening machine use for referring treated or enhanced diamonds as well as synthetics is the , and the definitive analytical machine is the produce by the DTC and supplied marketed by the GIA. All of the major diamond testing laboratories world wide are required to have these machines.

==See also==
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==Notes==
{{reflist|2}}

==References==
<div class="references-2column">
* David, Joshua (September 2003). . ''Wired'', issue 11.09.
* De Beers Group. . Retrieved ], ].
* Epstein, Edward Jay (February 1982). (subscription required). ''The Atlantic Monthly''.
* Epstein, Edward Jay (1982). (Complete book, includes "Chapter 20: Have you ever tried to sell a diamond?")
* Chaim Evevn-Zohar (2007). (Second edition of the book on the world diamond industry) Mining Journal Press.
* Eppler, W.F. ''Praktische Gemmologie''. Rühle-Diebner-Verlag, 1989
* Government of Gujarat (2004). . Retrieved ], ].
* Kjarsgaard, B.A. and Levinson, A. A. (2002). Diamonds in Canada. ''Gems & Gemology'', Vol. 38, No. 3, pp. 208&ndash;238.
* Kunz, George Frederick, ''Curious Lore of Precious Stones'', Lippincott Co., 1913
* Pagel - Theisen, Verena. ''Diamond Grading ABC: the Manual'' Rubin & Son, Antwerp, Belgium, 2001. ISBN 3-9800434-6-0
* Streeter - ''The Great Diamonds of the World'' , London, George Bell & Sons, 1882
* Taylor, W.R., Lynton A.J. & Ridd, M., (1990) ''American Mineralogist'', 75, pp. 1290–1310.
* Tolkowsky, Marcel (1919). ''Diamond Design: A Study of the Reflection and Refraction of Light in a Diamond.'' London: E. & F.N. Spon, Ltd. ( as edited by Jasper Paulsen, Seattle, 2001)
* Tyson, Peter (November 2000). . Retrieved ], ].
* United Nations Department of Public Information (], ]). . Retrieved ], ].
* Weiner, K.L., Hochleitner, R., Weiss, S., Voelstadt H. ''Diamant'', Lapis, München, 1994.
* Yarnell, Amanda (], ]). . '']'', vol. 82, no. 5, pp 26&ndash;31.
* American Museum of Natural History. . Retrieved ], ].
* Carnegie Institution.. Retrieved ], ].
* Williams, Gardner, ''The Diamond Mines of South Africa'', New York, B.F. Buck & Co., 1905
* World Diamond Council. . Retrieved ], ].
* Wise, Richard W. "Secrets Of The Gem Trade, The Connoisseur's Guide To Precious Gemstones". (2003) Brunswick House Press. Website of book:
*GIA . (2007) GIA
</div>

==External links==
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* Most of the books mentioned as references, found online here.

{{Allotropes of carbon}}
{{Jewellery Materials}}

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Revision as of 17:15, 28 April 2008

DIAMONDS ARE SHINY. ha ha ha !

REBELS WERE HERE