Chemical properties Purity 99.90 % min B2o3 36, 47 % min Physical properties Crystalline powder Molecular weight 381, 83 381, 83 Specific gravity 1, 73 gr/cm3 1, 73 gr/cm3 Bulk density 0, 812 gr/cm3 0, 750 gr/cm3 Fractions +1 mm 0, 8 % max +1 mm 0 % max -0, 060 mm 4 % max -0, 060 mm 50 % max 25-50 kgs bags/big-bags with or without pallets