... Sulfuret flake Molecular formula: Na2SAppearance: Thin flakes, yellow or red, soluble water, presenting strong alkaline solution, easily oxidized when ... exposed to air, poison. Specification:1. Red flakes-purity:60%,iron:1500ppm2. Yellow flakes purity:60%,iron ... leather, digestion auxiliary in paper-making also widely used in pigment and rubber industry, etc. Packing: 25kgs net weight/bag ...