Diamond

Apollo Diamond, based in Boston, produces nearly flawless single crystal diamond wafers and crystals for the optoelectronics, nanotechnology, and consumer gem markets. The company pioneered chemical vapor deposition (CVD) for the production of gem-sized cultured diamond crystals, leading to several U.S. patents on the process. Apollo Diamond"

Brilliant is one of the most used cuts for diamonds. Brilliant (diamond cut)"

Carbonado is a natural polycrystalline diamond found in alluvial deposits in Carbonado"

A conflict diamond (also called a blood diamond or a war diamond) is a diamond mined in a war zone and sold, usually clandestinely, in order to finance an insurgent or invading army's war efforts. Non-governmental organizations have also alleged the use of these diamonds in financing the September 11, attacks. Conflict diamond"

This article addresses the possible defects of a diamond crystal. For a broader discussion of diamonds, see diamond. For other uses of the word diamond, see diamond (disambiguation). Crystallographic defects in diamond"

The Cullinan Diamond, found by Frederick Wells, surface manager of the Premier Diamond Mining Company in Cullinan, Gauteng, South Africa on June 25 1905, is the largest rough gem-quality diamond ever found, at 3,106.75 carats (621.35 g). Although a carbonado found in Brazil weighed more than 3,600 carats (720 g), no gem-quality material could be extracted from it. The stone was named after Sir Thomas Cullinan, the owner of the diamond mine. Cullinan Diamond"

Detonation nanodiamond is diamond material that originates from a detonation. When an explosive mixture of TNT/ RDX (3/2) is detonated (5 GPa, 2000 °C) diamond particles with a diameter of 4 nm are formed. Detonation nanodiamond"

Diamond is 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 only be scratched by other diamonds, 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. Diamond"

Diamond clarity is a quality of diamonds relating to the existence and visual appearance of internal defects of a diamond called inclusions, and surface defects called blemishes. Clarity is one of the four Cs of diamond grading, the others being carat, color, and cut. Inclusions may be crystals of a foreign material or another diamond crystal, or structural imperfections such as tiny cracks that can appear whitish or cloudy. The number, size, color, relative location, orientation, and visibility of inclusions can all affect the relative clarity of a diamond. A clarity grade is assigned based on the overall appearance of the stone under 10x magnification. Diamond clarity"

A chemically pure and structurally perfect diamond is perfectly transparent with no hue, or color. However, in reality almost no gem-sized natural diamonds are absolutely perfect. 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 when more yellow hue is detectable, while intense pink or blue diamonds (such as the Hope Diamond) can be dramatically more valuable. Out of all colored diamonds, red diamonds are the rarest of all. Diamond color"

This article addresses the many styles of diamond cut. For a broader discussion of diamonds, see diamond. For other uses of the word diamond, see diamond (disambiguation). Diamond cut"

Diamond Cutting is the art, skill and, increasingly, science of changing a diamond from a rough stone into an attractive gem. It is possible only because the hardness of diamond varies widely according to the direction one is trying to cut or grind. Diamond cutting"

The Diamond District is an area of New York City found along 47th Street (between 5th Avenue and Avenue of the Americas) in the neighborhood of Midtown in the borough of Manhattan. The area is one of the three primary centers of the global diamond industry (along with Antwerp, Belgium and South Africa), as well as the premiere center for jewelry shopping in the city. Diamond district"

The Diamond Trading Company (DTC) is a London-based subsidiary of the De Beers Group, specializing in the sale and marketing of rough (uncut) diamonds. The company forms an essential part of De Beers' market control mechanism, maintaining an exclusive list of sightholders to which it sells all De Beers gem-grade diamonds coming to the market in a limited number of sales per year. Nicky Oppenheimer is chairman of DTC. Diamond Trading Company"

Eighternity is a cutting style and brand for round brilliant diamonds modelled after a pattern popularized by the EightStar Diamond Company. Similar to Hearts and arrows Eighternity is a form of the Super Ideal cut. Eighternity"

The Gemesis Corporation is a privately-held company founded by Carter Clarke in Sarasota, Florida. The corporation creates cultured diamonds using proprietary technology. Gemesis"

Hearts and arrows (H&A;) is a cutting style for round brilliant diamonds modelled after a pattern popularized by the EightStar Diamond Company. The pattern is a series of eight gray arrowheads when viewed from above the crown with one eye and eight heart shapes when viewed from below the pavilion. H&A; viewers eliminate incoming light from certain angles and cause the pattern to appear black or very dark gray. In order to display this pattern flawlessly, the diamond must have excellent symmetry of its major facets, and particular lengths of its lower girdle facets. Hearts and arrows"

The Kimberley Process Certification Scheme (KPCS) is a scheme designed to prevent conflict diamonds (also known as blood diamonds) entering the mainstream rough diamond market. The scheme was set up to try to assure consumers that by purchasing diamonds they were not financing war and human rights abuses. 98% of the world's trade in rough diamonds takes place in and between countries taking part in the scheme. Kimberley Process"

Kimberlite is an ultrabasic igneous rock composed of mica peridotite. Kimberlites are found as dikes and volcanic pipes which underlie and are the source for rare and relatively small explosive volcanoes. Kimberlite"

A number of large or extraordinarily colored diamonds have gained fame, both as exquisite examples of the beautiful nature of diamonds, and because of the famous people who wore, bought, and sold them. A partial list of famous diamonds in history follows. List of famous diamonds"

Marcel Tolkowsky ( 1899- 1991) was a member of a Belgian family of diamond cutters and an engineer by education. He is generally acknowledged as the father of the modern round brilliant diamond cut. Developed by Marcel Tolkowsky in 1919, the American Standard (also known as the American Ideal Cut, Tolkowsky cut, and Tolkowsky Brilliant) is the benchmark in North America. It was derived from mathematical calculations that considered both brilliance and fire of diamonds. Later modifications of round brilliants differ in minor ways. Marcel Tolkowsky"