Stannous Oxide used as Reducing Agent Intermediate in preparation of Stannous Salts in Plating & Glass Industries, Pharmaceuticals, Soft Abrasive Industries etc. Appearance: Brownish Black Powder. Tin Content as Sn: 87.50 - 88 %, Decomposes: 1080º C at 600 mm, Density (gmcc at 20º C): 6.30. Reaction: Reacts with Acids & Strong Bases.