... Residue on sieve ),% ≤0.1Specific gravity , g/cm32.67Melting point, oC980Losing temperature of crystal water, oC >320Refractive index1.58Application:1. Zinc borate ... Residue on sieve ),% ≤0.1Specific gravity , g/cm32.67Melting point , oC980Losing temperature of crystal water , oC >320Refractive index1.58Application:Because of its ...