Putty-powder

Chambers's Encyclopaedia, Volume 8: Peasant to Eoumelia, p. 501

Putty-powder is the binoxide or dioxide of tin, \text{SnO}_2. It is prepared from the scum or crude oxide which forms on the surface of melted tin, which is removed and purified by calcination, and then ground to powder. Putty-powder is used for polishing stone and glass, for making white enamel, and for giving glass an opaque colour.

Source scan(s): p. 0510