pumice stone

English Thesaurus

1. a light glass formed on the surface of some lavas; used as an abrasive (noun.substance)

hypernym	:	rock, stone,
definition	:	material consisting of the aggregate of minerals like those making up the Earth's crust (noun.substance)

derivation	:	pumice,
definition	:	rub with pumice, in order to clean or to smoothen (verb.contact)

derivation	:	pumice,
definition	:	rub with pumice, in order to clean or to smoothen (verb.contact)