Diamond

Town in Newton County, southwest Missouri; population (1990) 800. It is situated 19 km/12 mi southeast of Joplin. George Washington Carver, the noted scientist long associated with Alabama's Tuskegee Institute, was born here. His home, to the southwest of the town, is now part of the George Washington Carver National Monument.


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Experiments

Using a device known as a diamond-anvil cell, a moderate force applied to the small tips of two opposing diamonds can be used to attain extreme pressures of millions of atmospheres or more, allowing scientists to subject small amounts of material to conditions that exist deep within planet interiors.

In 1999 US scientists turned a diamond into a metal using a very powerful laser to compress it.

Cutting

Rough diamonds are often dull or greasy before being polished; around 50% are considered ‘cuttable’ (all or part of the diamond may be set into jewellery). Gem diamonds are valued by weight (carat), cut (highlighting the stone's optical properties), colour, and clarity (on a scale from internally flawless to having a large inclusion clearly visible to the naked eye). They are sawn and polished using a mixture of oil and diamond powder. The two most popular cuts are the brilliant, for thicker stones, and the marquise, for shallower ones. India is the world's chief cutting centre.

Noted rough diamonds include the Cullinan, or Star of Africa (3,106 carats, over 500 g/17.5 oz before cutting, South Africa, 1905); Excelsior (995.2 carats, South Africa, 1893); and Star of Sierra Leone (968.9 carats, Yengema, 1972).

Practical uses

Because diamonds act as perfectly transparent windows and do not absorb infrared radiation, they were used aboard NASA space probes to Venus in 1978. The tungsten carbide tools used in steel mills are cut with industrial diamond tools.

Varieties

There are four chief varieties of diamond: well-crystallized transparent stones, colourless or only slightly tinted, valued as gems; boart, poorly crystallized or inferior diamonds; balas, an industrial variety, extremely hard and tough; and carbonado, or industrial diamond, also called black diamond or carbon, which is opaque, black or grey, and very tough. Industrial diamonds are also produced synthetically from graphite. Some synthetic diamonds conduct heat 50% more efficiently than natural diamonds and are five times greater in strength. This is a great advantage in their use to disperse heat in electronic and telecommunication devices and in the production of laser components.

Sources

Diamonds may be found as alluvial diamonds on or close to the Earth's surface in riverbeds or dried watercourses; on the sea bottom (off southwest Africa); or, more commonly, in diamond-bearing volcanic pipes composed of ‘blue ground’, kimberlite or lamproite, where the original matrix has penetrated the Earth's crust from great depths. They are sorted from the residue of crushed ground by X-ray and other recovery methods

History

Diamonds were known before 3000 BC and until their discovery in Brazil in 1725, India was the principal source of supply. Present sources are Australia, the Democratic Republic of Congo (formerly Zaire), Botswana, Russia (Yakut), South Africa, Namibia, and Angola; the first two produce large volumes of industrial diamonds. Today, about 80% of the world's rough gem diamonds are sold through the De Beers Central Selling Organization in London.

diamond

Generally colourless, transparent mineral, an allotrope of carbon. It is regarded as a precious gemstone, and is the hardest substance known (10 on the Mohs scale). Industrial diamonds, which may be natural or synthetic, are used for cutting, grinding, and polishing.

Diamond crystallizes in the cubic system as octahedral crystals, some with curved faces and striations. The high refractive index of 2.42 and the high dispersion of light, or ‘fire’, account for the spectral displays seen in polished diamonds.

DaimlerChrysler Corp. v. Cuno,

547 U.S. ___ (2006) was a case decided by the Supreme Court of the United States involving the standing of taxpayers to challenge state tax laws in federal court. The Court unanimously ruled that state taxpayers did not have standing under Article III of the United States Constitution to challenge state tax or spending decisions simply by virtue of their status as taxpayers.[1] Chief Justice John Roberts delivered the majority opinion (his fifth on the Court), which was joined by all of the justices except for Ruth Bader Ginsburg, who concurred separately. Background of the case

Diamond

Diamond -


One of five pedagogical languages based on Markov algorithms, used in "Nonpareil, a Machine Level Machine Independent Language for the Study of Semantics", B. Higman, ULICS Intl Report No ICSI 170, U London (1968). (cf. Brilliant, Nonpareil, Pearl[3], Ruby[2]).


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diamond

token of affection, e.g., for engagement. [Gem Symbolism: Jobes, 440–441]
See : Love
Allusions—Cultural, Literary, Biblical, and Historical: A Thematic Dictionary. Copyright 2008 The Gale Group, Inc. All rights reserved.

diamond

April birthstone, most reflective of gems. [Gem Symbolism: Jobes, 440–441]
See : Brightness

diamond

April. [Am. Gem Symbolism: Kunz, 319–320]
See : Birthstones

diamond

1.
a. a colourless exceptionally hard mineral (but often tinted yellow, orange, blue, brown, or black by impurities), found in certain igneous rocks (esp the kimberlites of South Africa). It is used as a gemstone, as an abrasive, and on the working edges of cutting tools. Composition: carbon. Formula: C. Crystal structure: cubic
b. (as modifier): a diamond ring
2. Geometry
a. a figure having four sides of equal length forming two acute angles and two obtuse angles; rhombus
b. rhombic
3.
a. a red lozenge-shaped symbol on a playing card
b. a card with one or more of these symbols or (when plural) the suit of cards so marked
4. Baseball
a. the whole playing field
b. the square formed by the four bases
5. black diamond a figurative name for coal
6. rough diamond an unpolished diamond
www.adiamondisforever.com
www.amnh.org/exhibitions/diamonds
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

diamond

Mineral composed of pure carbon, the hardest naturally occurring substance known and a valuable gemstone. Diamonds are formed deep in the Earth by tremendous pressures and temperatures over long periods of time. In the crystal structure of diamond, each carbon atom is linked to four other, equidistant, carbon atoms. This tight crystal structure results in properties that are very different from those of graphite, the other common form of pure carbon. Diamonds vary from colourless to black and may be transparent, translucent, or opaque. Most gem diamonds are transparent and colourless or nearly so. Colourless or pale blue stones are most valued, but most gem diamonds are tinged with yellow. Because of their extreme hardness, diamonds have important industrial applications. Most industrial diamonds are gray or brown and are translucent or opaque. In the symbolism of gemstones, the diamond represents steadfast love and is the birthstone for April.

For more information on diamond, visit Britannica.com. Britannica Concise Encyclopedia. Copyright © 1994-2008 Encyclopædia Britannica, Inc.

The Diamond Cartel

The discoveries of 1870–71 in South Africa led to a great number of prospectors staking out claims and securing the diamonds by open-pit or quarry mining. The damage caused by floods and mudslides, unavoidable when there were so many different claims, was an important factor in the series of amalgamations carried on by Cecil Rhodes Rhodes, Cecil John (sĕs`ĭl, rōdz), 1853–1902, British imperialist and business magnate.
..... Click the link for more information. and Barnett Barnato Barnato, Barnett (bärnä`tō), 1852–97, South African financier, b. London.
..... Click the link for more information. . Rhodes brought about the merging of their interests in the De Beers Consolidated Mines, Ltd., which established (1889) an effective monopoly over the diamond industry. Loss of diamonds by theft was reduced through the passage of the so-called I.D.B. (Illicit Diamond Buying) Act, which limited the trade to licensed buyers and imposed penalties for the possession of uncut stones without a license. Thefts were further curtailed by the institution of compounds in which the workers live while employed by the company and which they leave only after being thoroughly searched.

Most of the major diamond producers belong to, or have cooperated with, the De Beers–led marketing cartel, formed to maintain the price of diamonds at a high level. De Beers, under Harry Oppenheimer's leadership (1957–84), maintained its dominant position in the industry by using its numerous worldwide companies to buy up new sources of diamonds and to control distribution of industrial diamonds and production of synthetic ones. In the last decades of the 20th cent., however, De Beers' hold over the unpolished diamond market decreased, and in 2000 the company announced it would end to its policy of controlling diamond prices through hoarding and shift its focus to increasing sales.

Diadem or tiara of diamonds, gold, and silver with 25 five-point stars, graduated in size, set "en tremblant," containing 502 brilliants, 60 rose cuts; the central diamond of the largest star is 21.60 carats. By Estevao de Sousa, Lisbon, 1863-1866. Commissioned by Queen Maria Pia of Portugal (1847-1911). Both loaned by the National Palace of the Ajuda Museum, Lisbon.

JEWELRY GEMS

Riviere - a necklace "river" of diamonds. With 55 graduated diamonds, total weight 118 carats, set in silver on a gold chain. By Ambrosio Gottlieb Polett, Lisbon, second half of 18th century. Loaned by the National Palace of the Ajuda Museum, Lisbon.

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JEWELRY/GEMS

Part of the Aurora Collection of 260 naturally colored diamonds from worldwide sources representing the variety of fancy colors in diamonds. The stones range from 0.13 to 2.88 carats, and total 231.73 carats. Loaned by Aurora Gems, Inc., New York.

Diamond Color

Cut : Color : Clarity : Clarity Enhacement : Carat Weight : Certification : Caring : Diamond Shapes

Diamond Color
The color of a diamond depends on the quantity and nature of trace elements within the stone and how these elements originated. Most commercially available diamonds range in color from colorless to pale yellowish. There are other colors of diamonds known as "fancy diamonds" which can be pink, blue, green, yellow, brown and even black.

The GIA (Gemological Institute of America) provides a letter scale in which diamonds are graded based on their color. The following diagram illustrates the range of color grades:



NOTE: The colors on this chart are for demostration purposes only. Since all monitors display colors diferrently, what you see on this chart may not represent the exact color grade.

Diamonds that are graded in the D-F range are the rarest and consequently most valuable. In reality, diamonds in the G-K range have such a small amount of color that the untrained eye can not see it and as such offer a great value. In order to provide our customers with the finest possible selection of inventory, you will not find any diamonds rated below P in color on the web site. Fancy color diamonds are available in their own section and do not follow the letter grading conventions in the chart above.

Fluorescence
This characteristic of a diamond causes a slight blue glow when the stone is exposed to intense, direct ultraviolet light. This type of light can typically be found in nightclubs. A small amount of ultraviolet light comes directly from the sun.There are differing opinions on fluorescence and whether to avoid it or not. We believe it comes down to a matter of personal taste and does not affect the value of the diamond.

See The Diamond Before Paying

We believe that buying a diamond is a big decision and we want you to see your diamond in person before paying for anything. Learn more about how Yehuda.com works

Making Diamonds Look Better

Now you can afford the largest, most beautiful diamonds you've dreamed of thanks to the Yehuda diamond clarity enhancement process.

Browse Online, Buy In Person

Select any two clarity enhanced loose diamonds or pieces of finished diamond jewelry from our site and complete an online request. You will then receive an email with the contact information of the authorized Yehuda jeweler in your area. Give them a call and schedule an appointment. When we receive notice from the jeweler that an appointment has been scheduled, we will ship the exact diamonds you requested. Then on the day of your appointment, you can drop in to your local jewelry store and see the diamond face-to-face, touch it, inspect it with a jeweler's loupe and compare it to other more expensive non-enhanced diamonds.

If you decide to buy one of the diamonds we sent, you will pay the low internet price you see online, but get a knowledgable local jeweler's service to answer questions, mount the diamond, size the ring and complete your purchase.

Merchant Information

Located in the world famous New York City Diamond District, S.E.A. Wave Diamonds has been dedicated to exceeding the needs and expectations of our loyal customers and clientele since 1995. Yet, our passion for handcrafting premium designer jewelry far surpasses that timeframe.





As a family owned and operated business, S.E.A. Wave Diamonds was built from the ground up cultivated by a fondness for and commitment to designing and creating the finest luxury jewelry items on the market. More than a decade later, the principles of hard work, honesty and integrity that drove us then have not changed. In fact, our dedication to our customers is matched only by the unparalleled brilliance of our collection.


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Item: Diamond (Specimen): NATURAL Diamond Crystal In Kimberlite Matrix

This unique item is sold. Code#: diam118aWeight: 23.5 gramsSize: Approximately 35mm x 29mmLocation: Udachnay mine, Siberia ( Russia ).Price: $2050.00 This natural, beautiful white diamond crystal has very good clarity and is still enbedded in the kimberlite host rock that brought it to the surface of the earth. The kimberlite has numerous eye visible olivine crystals throughout as well as other associated minerals. The size of the diamond crystal is approximately 7.0mm x 7.0mm and appears to be a twinned crystal. The overall size of the host rock is 35mm x 29mm, and weighs over 23.5 grams.The specimen was recovered at about the 500 meter depth of the Udachnay pipe, which is located 600 K M to the north from the city of Mirniy. We estimate the diamond crystal to weigh over 1.5 carats. The photo at left shows a cloes-up, see also a full-view photo.

Item: Diamond (Specimen): NATURAL Diamond Crystal In Kimberlite Matrix

Code#: diam117aWeight: 36.3 gramsSize: Approximately 45mm x 27mmLocation: Udachnay mine, Siberia ( Russia ).Price: $1995.00 This natural, beautiful white diamond crystal has mostly good clarity and is still enbedded in the kimberlite host rock that brought it to the surface of the earth. The kimberlite has numerous eye visible olivine crystals throughout as well as other associated minerals. The size of the diamond crystal is approximately 6.8mm x 6.8mm and the overall size of the host rock is 45mm x 27mm, and weighs over 36 grams.The specimen was recovered at about the 500 meter depth of the Udachnay pipe, which is located 600 K M to the north from the city of Mirniy. We estimate the diamond crystal to weigh nearly 1.5 carats. The photo at left shows a cloes-up, see also a full-view photo.

Item: Natural Greenish-Gray Diamond Crystal, 2.82 carats

This unique item is sold. Code#: diam120Weight: 2.82 caratsSize: Approximately 8.8 x 7.0 x 6.5mmLocation: natural diamond rough mined in CongoPrice: $183.30 This natural cubic diamond crystal specimen is translucent with greenish-gray natural color in good condition overall.

Auction for Dickens' diamond ring

A diamond ring given to the author Charles Dickens by his poet friend Lord Alfred Tennyson has been put up for auction in Herefordshire.
The 0.9 carat diamond ring is inscribed with the message "Alfred Tennyson to Charles Dickens 1854"- the same year in which he published Hard Times.
It was listed to be sold by auctioneer Nigel Ward & Co at its salerooms in Pontrilas, Herefordshire.
The ring has a guide price of between £25,000 to £35,000.
'Ring's custodians'
Papers detailing the ring's provenance were also due to be auctioned.
These include a list of valuables believed to have been written by the author's son Hector Charles Bulwer Lytton Dickens in the Bay of Biscay, on 14 April, 1924.
Hector wrote: "Large diamond ring belonging to my father bought by me from my brother A.T. Dickens (Alfred D'Orsay Tennyson Dickens) in Melbourne in 1890. Engraved inside 'Alfred Tennyson to Charles Dickens 1854', the year of my birth."
The auctioneers said the document was believed to be genuine based on the fact that Alfred Dickens is known to have incurred large debts and emigrated to Australia, where he later married.
Hector Dickens' will was among the papers to be auctioned, showing how the ring was passed down among the family to its current owner who is putting it up for auction

Diamond exports plunge 90%

BRIAN BENZAStaff Writer

Diamond exports plunged by close to 90 percent in the four months between August and November 2008 as the global recession hit demand for luxury goods, figures availed by the Central Statistics Office (CSO) reveal.




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According to the CSO, diamond exports which amounted to P3.3 billion in August, fell to P2.3 billion in November and to P821 million in October before plummeting to a mere P371 million in November as a result of falling demand and weakening prices.
Global demand for rough diamonds, which are the mainstay of the economy, is expected to drop by some 60 percent this year and the government has already estimated that revenues will be cut by over 50 percent.The latest figures call for serious belt-tightening measures.
In the 2009/10 budget, the government announced that it will pump P10 billion into the economy for developmental projects in a bid to boost economic activity, a decision which has been labelled ambitious by some analysts in view of the global economic crisis. The irony is that Debswana was struggling to meet demand for diamonds barely six months ago. Factors militating against Botswana include the fact that the country is a net importer of goods, particularly fuel and food, is economically dependent on mineral exports, especially diamonds, and its growth prospects are largely built around investment in minerals.According to the latest trade figures from the CSO, a 55-percent plunge in diamond exports in November led to a P2 billion-trade deficit in the same month.
November 2008 registered a trade deficit of P2,001.7 million, being the fifth month to register a deficit during the first eleven months of last year. Deficits were also recorded in April, May, July and October with values of P113.4 million, P905.7 million and P393.3 million and P1, 525.5 million respectively. "Total exports were valued at P1,081.4 million during November 2008, giving a decline of 39.2 percent (P697.6 million) from P1,779.0 million recorded during the previous month (October 2008)," said the CSO report. The November 2008 total exports declined by 53.2 percent (P1, 229.8 million) as compared to the value of P2, 311.2 million recorded during November 2007. On the other hand, November 2008 total imports were valued at P3, 083.1 million, having decreased by 6.7 percent (P 221.4 million) from the October 2008 value of P3, 304.5 million. "Comparison of total imports value for November 2008 to the value recorded during the same month in 2007 shows an increase of 6.1 percent (P177.3 million), from P2,905.8 million recorded during November 2007 to P3, 083.1 million recorded during November 2008." The P2 billon deficit is certainly going to eat into Botswana's foreign exchange reserves, which were reported by the government to be standing at over P72 billion - the equivalent of 30 months' import cover.
While imports have consistently been around P3 billion, exports have drastically plunged from P4.2 billion in August to P1 billion in November, a development that will exert a significant amount of pressure on the forex reserves.According to the figures, the value of diamond exports has been consistently declining since September 2008, resulting in an increase in percentage contributions made by other major exports.As the contribution of diamonds fell from 46 percent to 34 percent between October and November and copper and nickel from 31 percent to 26 percent, textiles grew from 10 percent to 17 percent while machinery and equipment rose from 2.4 percent to 9.9 percent.
However, looking on the bright side, analysts say long-term fundamentals of the industry continue to hold considerable promise inspite of the current turmoil. "The diamond industry is now in a stabilising phase where stocks, prices and supply and demand have to find a new equilibrium," renowned Israeli diamond industry expert and journalist, Chaim Even-Zohar said in a recent article. "This may take 12-14 months. In that period, demand for rough diamonds will plunge by some 60 percent. This is inevitable. However, miners like DiamonEx - if they survive - are not losing revenues; they are merely delaying income to better times.
"Unfortunately, in this restructuring and stabilising process, 'pain' will not be shared equally. Botswana will be hurting more than many other players - but we believe that demand for rough diamond will again grow in the second/third quarter of 2010. In an industry used to concepts like 'forever', this isn't too far ahead."

The Very Highest Quality Diamond Information...

Diamond Types

Diamond Types
The Very Highest Quality Diamond Information...
Diamond Types

Diamonds Index

Fancy Coloured Diamonds are Very Rare

Uncut Diamonds of Many Colours
Diamond TypesDiamonds can be scientifically classified into 4 types, known as type 1a, 1b, 2a, and 2b.Diamonds are made of carbon, and are extremely pure, but in almost all diamonds there are tiny proportions of other elements, interspersed within the carbon as part of their crystal structure. These "impurities" are not what are known as inclusions, and are so small as to be invisible even under a very powerful microscope.
Type 1 DiamondsType 1 diamonds contain nitrogen. About 98% of all diamonds are type 1a
Type 1aIf the nitrogen atoms are clustered together within the carbon lattice, then the diamond is said to be a Type 1a diamond. Because these diamonds absorb blue light, they can have a pale yellow or brown color. 98% of diamonds are Type 1a.
Type 1bIf the nitrogen atoms are evenly spread out throughout the carbon lattice, then the diamond is said to be a Type 1b diamond. These diamonds absorb green light as well as blue light, and have a darker color than type 1a diamonds. Depending on the precise concentration and spread of the nitrogen atoms, these diamonds can appear deep yellow ("canary"), orange, brown or greenish. Less then 0.1% of diamonds belong to Type 1b.
Type 2Type 2 are diamonds that absorbed no, or very few, nitrogen atoms.
Type 2aThese diamonds can be considered as the "purest of the pure" - they contain no, or minuscule amounts of impurities and are usually colorless. Unless, that is, the carbon tetrahedrons that make up the diamond were twisted and bent out of shape while the diamond rose to the surface of the earth. An imperfect carbon lattice will make the diamond absorb some light, which will give it a yellow, brown or even pink or red color. 1-2% of diamonds belong to Type 2a.
Type 2bThese diamonds contain no nitrogen - but they do contain boron, which absorbs red, orange and yellow light. These diamonds therefore usually appear to be blue, although they can also be grey or nearly colorless. All naturally blue diamonds belong to Type 2b, which makes up 0.1% of all diamonds.
Summary of Diamond Classification
Type
Prevalence
Feature
Colours
1a
98%
Clustered Nitrogen Atoms
Colourless, Yellow
1b
0.1%
Scattered Nitrogen Atoms
Yellow, Orange, Brown
2a
1 - 2%
Highly Pure Carbon
Colourless, Yellow, Brown, Pink, Purple
2b
0.1%
Boron Atoms
Blue, Gray
Green DiamondsGreen diamonds are a separate case: these diamonds can contain clustered nitrogen atoms or they can contain no nitrogen atoms - what gives them their color is that they have been bombarded by nuclear rays during their growth. This bombardment makes them absorb magenta wavelengths, which gives them their green color. These diamonds are extremely rare.
Type 1 or I, Type 2 or IISome works cite the diamond types as Ia, Ib, IIa, and IIb, rather than 1a, 1b, 2a, and 2b. As you can see, we have chosen to use Arabic numerals rather than Latin.
Diamond 4C's Tour - Next Stop - Clarity
Diamond Glossary - An A to Z of Diamonds

The Middle Ages

During the Middle Ages more attention was paid to the worth of diamonds, rather than the mystical powers surrounding them. Due to the heightened public awareness of the value of diamonds, mine owners perpetuated myths that diamonds were poisonous. This was to prevent the mineworkers swallowing the diamonds in an attempt to smuggle them out of the mines.
The popularity of diamonds surged during the Middle Ages, with the discovery of many large and famous stones in India, such as the Koh-I-Noor and the Blue Hope. Today India maintains the foremost diamond polishing industry in the world.