• WordNet 3.6
    • n rottenstone a weathered and decomposed siliceous limestone; in powdered form it is used in polishing
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Century Dictionary and Cyclopedia
    • n rottenstone An argillaceous or silicious limestone which by weathering has become soft and friable, the calcareous part having been wholly or in part removed. This material when pulverized forms a cheap and efficient substance for use in polishing the softer metals.
    • rottenstone To polish with rottenstone.
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Chambers's Twentieth Century Dictionary
    • Rottenstone a soft and earthy stone powdered to polish brass, &c
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Chambers's Twentieth Century Dictionary


In literature:

Bath brick or rottenstone may be used for polishing.
"Burroughs' Encyclopaedia of Astounding Facts and Useful Information, 1889" by Barkham Burroughs
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" by C. K. Leith