how silicon is made, making, history, used
raw materials silicon metal is made from the reaction of silica (silicon dioxide, sio2) and carbon materials like coke, coal and wood chips. silica is typically received in the form of metallurgical grade gravel. this gravel is 99.5% silica, and is 3 x 1 or 6 x 1 in (8 x 3 cm or 15 x 3 cm) in size. the coal is usually of low ash content (1 3% to minimize