... drilling grade API 13 BaSO4:85~98% Whiteness 70~95% Water solubles 0.2% max Specification S.G4.2 ... 13 Specification: Specification ASpecification BSpecification CBaSO4 content (%)75~90%95%98%Specific gravity (g/cm2)4.0~4.154.2 ... ~4.254.3~4.4Whiteness (%)70~85 %90~95 %95~98 %Moisture (%)0.2 %max0.2~0.01%Fe2O3 ... ~1.4Density (g/cm3%)2.1~2.7PH value 7.9~8.1 Size: 1) powder : 325 ,400, 1250, 2500, 3000 ...