Very light weight sedimentary rock composed of the remains of diatoms.
a light soil consisting of siliceous diatom remains and often used as a filtering material
A light-colored, soft rock composed of the siliceous skeletons of diatoms (water-dwelling organisms)
Diatomite, or diatomaceous earth, is a siliceous sedimaentary rock formed from the accumulations of diatoms or other nanoplankton.
Another name for diatomaceous earth.
a light, porous rock consissting of the fossil remains of diatoms, used as an abrasive, insulator, filter, etc. [AHDOS