Sodium Hydrosulfide 70%, High Assay, Good color, competitive price, supply by the really ... ) Appearance: Colorless or light yellow, volatile, flammable liquid. 2) Assay: 70.00% min. 3) Insolubles in Water: 0.005% max. 4 ... ore. As sulfide dye agent in synthetic fibre. Sodium Hydrosulfide 70%