Background

Moissanite was discovered by Henri Moissan while examining rock samples from a meteor crater located in Canyon Diablo, Arizona in 1893. First he identified the crystalls as diamonds, but in 1904 he identified this new mineral and called it silicon carbide. Silicon carbide was named moissanite in honor of Moissan later on in his life. Until the 1950s no other source, apart from meteorites, had been found. Later it was found as inclusion in kimberlite from a diamond mine in Yakutia in 1959, and in the Green River Formation in Wyoming in the year before. The discovery in the Canyon Diablo meteorite and other places was challenged for a long time to be carborund contamination from human abrasive tools. The existence of moissanite in nature was questioned even in 1986 by Charles Milton, an American geologist.

Geological occurrence

Moissanite has been discovered in a variety of places from upper mantle rock to meteorites. Discoveries have shown that moissanite occurs naturally as inclusions in diamonds, xenoliths, and ultramafic rocks such as kimberlite and lamproite. They have also been identified in presolar meteorites formed with grains from supernovae or red giants, called carbonaceous chondrites.

Composition

All applications of silicon carbide today use synthesized material. Silicon carbide was first synthesized by Jons Jacob Berzelius, who is best known for his discovery of silicon. Years later, Acheson produced suitable minerals that could substitute diamond as an abrasive and cutting material. He mixed coke and silica in a furnace and found a crystalline product characterized by a great hardness, refractability, and infusibility, which was shown to be a compound of carbon and silicon. Since naturally existing moissanite is so rare, synthetic silicon carbide is used for scientific applications and in jewelry sales too. The presence of nitrogen in the raw materials and during the creation process causes moissanite to have a slight green or yellow tint. As of August 2008, Charles and Colvard are able to produce near colorless moissanite similar to about a G or H rating on the GIA scale.Fact: date=August 2008

Structure

The structure of moissanite is one of its greatest properties. Similar to the diamond structure, moissanite's structure gives it great strength, making it useful for testing applications and microelectronics. The structure of elements is held together with strong covalent bonding that gives moissanite its distinctive strength along with other properties that rival diamond. All SiC minerals for testing purposes are synthetically made, due to the rarity of the natural existence of the mineral. Moissanite has little to no anisotropies occurring with in the crystal structure, thus giving it the ability to withstand high pressures and temperatures.