What is "putty powder"

Stannic \Stan"nic\ (-n[i^]k), a. [L. stannum tin: cf. F. stannique.] (Chem.) Of or pertaining to tin; derived from or containing tin; specifically, designating those compounds in which the element has a higher valence as contrasted with stannous compounds. Stannic acid.

1. A hypothetical substance, Sn(OH)4, analogous to silicic acid, and called also normal stannic acid.

2. Metastannic acid.

   Stannic chloride, a thin, colorless, fuming liquid, SnCl4, used as a mordant in calico printing and dyeing; -- formerly called spirit of tin, or fuming liquor of Libavius.

   Stannic oxide, tin oxide, SnO2, produced artificially as a white amorphous powder, and occurring naturally in the mineral cassiterite. It is used in the manufacture of white enamels, and, under the name of putty powder, for polishing glass, etc.

n. An oxide of tin, or of tin and lead in various proportions, used in polishing glass, metal, precious stones, etc.