Diamond artificial/synthetic

Dintrophenol diamond mfg., synthetic Hexachloroethane diamonds, artificial Thallium (I) carbonate... 

Diamonds are another allotrope whose crystal structure is similar to graphite. Natural diamonds were formed under higher pressure and extreme temperatures. Synthetic diamonds have been artificially produced since 1955. 

Spinel is a colorless magnesium aluminate (MgAl204) of cubic structure. It is hard and durable, but, like white sapphire, it is not a good diamond substitute because it has a low refractive index and lacks brilliance. However, it is readily doped to produce other gems of various colors. Artificial ruby, for example, is often natural red spinel, and most synthetic blue sapphires on the market are actually blue spinel. 

Apart from naturally occurring diamond there is by now a variety of artificial carbon materials that feature diamond structure as well. These include the synthetic diamond generated by high pressure and temperature, but also films, polycrystalline materials resembling the carbonados (Section 1.3.2) and the so-called... 

Diamonds can now be synthesized to weigh more than 0.6 g [3 carats (ct)]. This is an art for the color and clarity. The production of gem quality synthetic diamonds (Section 29.14) results in a deep yellow color. Colored diamonds tend to be more valuable than colorless ones simply because they are more rare. The Dresden Green diamond weighs 40.70 ct and is the largest known green diamond in the world. Natural red, pink, and yellow diamonds can also command prices of near 1M per ct. The danger is that diamonds can also be artificially colored by irradiating them diamond was perhaps the first irradiated gem. Blue B-doped diamond is a semiconductor while blue... 

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