rottenstone

[ rot-n-stohn ]
/ ˈrɒt nˌstoʊn /

noun

a friable stone resulting from the decomposition of a siliceous limestone, used as a powder for polishing metals.

Origin of rottenstone

First recorded in 1670–80; rotten + stone

Example sentences from the Web for rottenstone

British Dictionary definitions for rottenstone

rottenstone
/ (ˈrɒtənˌstəʊn) /

noun

a much-weathered limestone, rich in silica: used in powdered form for polishing metal