The silicon carbide found in space and in meteorites is almost exclusively the beta-polymorph. It is a common form of stardust found around carbon-rich stars, and examples of this stardust have been found in pristine condition in primitive (unaltered) meteorites. While rare on Earth, silicon carbide is remarkably common in space. Moissan's discovery of naturally occurring SiC was initially disputed because his sample may have been contaminated by silicon carbide saw blades that were already on the market at that time. Ferdinand Henri Moissan, after whom the material was named in 1905. Natural moissanite was first found in 1893 as a small component of the Canyon Diablo meteorite in Arizona by Dr. Virtually all the silicon carbide sold in the world, including moissanite jewels, is synthetic. Naturally occurring moissanite is found in only minute quantities in certain types of meteorite, corundum deposits, and kimberlite. Natural occurrence Moissanite single crystal (≈1 mm in size) SiC is used in semiconductor electronics devices that operate at high temperatures or high voltages, or both. Large single crystals of silicon carbide can be grown by the Lely method and they can be cut into gems known as synthetic moissanite.Įlectronic applications of silicon carbide such as light-emitting diodes (LEDs) and detectors in early radios were first demonstrated around 1907. Grains of silicon carbide can be bonded together by sintering to form very hard ceramics that are widely used in applications requiring high endurance, such as car brakes, car clutches and ceramic plates in bulletproof vests. A semiconductor, it occurs in nature as the extremely rare mineral moissanite, but has been mass-produced as a powder and crystal since 1893 for use as an abrasive. Silicon carbide ( SiC), also known as carborundum ( / ˌ k ɑːr b ə ˈ r ʌ n d əm/), is a hard chemical compound containing silicon and carbon.
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