rottenstone

rottenstone [rot-n-stohn] ExamplesWord Origin noun

1. 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 Examples from the Web for rottenstone Historical Examples of rottenstone

Tripoli (and rottenstone) are used in polishing powders and scouring soaps as well as for filter blocks and many other purposes.

The Economic Aspect of Geology

C. K. Leith

The unpainted surfaces will be kept clean and bright with rottenstone and oil or “Putz-pomade.”

The Gunner’s Examiner

Harold E. Cloke

Polishing is effected by wooden wheels fed with wet pumice-powder and rottenstone and by brushes fed with moistened putty-powder.

Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 1

Various

British Dictionary definitions for rottenstone rottenstone noun

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