Tin Tungstates

Stannous tungstate, SnWO₄.6H₂O, is obtained as a yellow powder by mixing solutions of sodium tungstate and stannous chloride. When a solution of ammonio-stannic chloride is added to a solution of ammonium paratungstate, a white flocculent precipitate is formed, presumably of stannic tungstate. It is soluble in excess of the tin salt.