... well as cutting and making jewelry, jade, agate. ♦ Grinding of gray cast iron, white cast iron, bronze, brass, ore, bone, glass ... # Sic>90% standard of P:P80-2500#. SymbolScriesGrit SizeChemical Properties % Grit SizeSicF.CFe2O3C F 12#-90# 100#-180# 220# -240# w63 ...