出典:Wiktionary
rottenstone (countable かつ uncountable, 複数形 rottenstones)
出典:『Wiktionary』 (2013/12/21 04:40 UTC 版)
rotten stone
出典:Wikipedia
出典:『Wikipedia』 (2011/03/06 23:00 UTC 版)
Rotten stone, sometimes spelled as one word, and also known as tripoli, is fine powdered rock used as a polishing abrasive in woodworking. It is usually weathered limestone mixed with diatomaceous, amorphous, or crystalline silica. It has similar applications to pumice, but it is generally sold as a finer powder and used for a more glossy polish after an initial treatment with coarser pumice powder.