A light, porous type of pyroclastic igneous rock, formed during explosive volcanic eruptions when liquid lava is ejected into the air as a froth containing masses of gas bubbles. As the lava solidifies, the bubbles are frozen into the rock.
A fine clay, rich in kaolinite, used in ceramics, paper-making, etc.
(transitive) To abrade or roughen with pumice.
A very pure white clay, ordinarily in the form of an impalpable powder, and used to form the paste of porcelain; China clay; porcelain clay. It is chiefly derived from the decomposition of common feldspar.
A very light porous volcanic scoria, usually of a gray color, the pores of which are capillary and parallel, giving it a fibrous structure. It is supposed to be produced by the disengagement of watery vapor without liquid or plastic lava. It is much used, esp. in the form of powder, for smoothing and polishing. Called also pumice stone.
a fine usually white clay formed by the weathering of aluminous minerals (as feldspar); used in ceramics and as an absorbent and as a filler (e.g., in paper)
a light glass formed on the surface of some lavas; used as an abrasive
Pumice ( ), called pumicite in its powdered or dust form, is a volcanic rock that consists of highly vesicular rough textured volcanic glass, which may or may not contain crystals. It is typically light colored.