Metallurgical Grade Specs.: ( 1) CaF2: 75% min SiO2: 24% max ( 2) CaF2: 80% min SiO2: 19% max ( 3) CaF2: 85% min SiO2: 14% max ( 4) CaF2: 88% min SiO2: 11% max ( 5) CaF2: ....