Abstract
Silicon carbide was formed under various time‐temperature conditions from mixtures of silica and carbon and of silicon and carbon. The products were examined by x‐ray diffraction, electron and optical microscopy, and chemical analysis. It was found that (a) primary silicon carbide, which is always beta 
, could be formed as low as 525°C when carbon and silicon were contained in a low melting alloy of aluminum and zinc; (b) beta 
is stable to near 2100°C; (c) under certain experimental conditions beta 
showed no significant crystal growth when held for 44 hours at 1400°C and only small growth (microscopic) up to 2100°C; and (d) that the change from beta to alpha silicon carbide is monotropic, and is complete after a few minutes at 2300°C.