Silicon carbide, also known as carborundum, is a compound of silicon and carbon that occurs naturally as the mineral moissanite. It was first produced synthetically in 1891 by Edward Acheson while attempting to make diamond. Silicon carbide exists in many crystalline forms called polytypes, with alpha silicon carbide being the most common. It has excellent physical properties like high hardness, thermal conductivity, resistance to acids and alkalis. Silicon carbide is produced commercially by heating quartz sand and carbon in an electric resistance furnace above 2000°C. It has many applications due to its properties, including use as an abrasive, in automotive brakes and clutches, semiconductors, heating elements