Diatomaceous earth ( /ˌdaɪ.ətəˌmeɪʃəs ˈɜrθ/) also known as D.E., diatomite, or kieselgur/kieselguhr, is a naturally occurring, soft, siliceous sedimentary rock that is easily crumbled into a fine white to off-white powder. It has a particle size ranging from less than 3 micrometre to more than 1 millimeter, but typically 10 to 200 micrometres. This powder has an abrasive feel, similar to pumice powder, and is very light as a result of its high porosity. The typical chemical composition of oven-dried diatomaceous earth is 80 to 90% silica, with 2 to 4% alumina (attributed mostly to clay minerals) and 0.5 to 2% iron oxide.
Diatomaceous earth consists of fossilized remains of diatoms, a type of hard-shelled algae. It is used as a filtration aid, mild abrasive in products including toothpaste, mechanical insecticide, absorbent for liquids, matting agent for coatings, reinforcing filler in plastics and rubber, anti-block in plastic films, porous support for chemical catalysts, cat litter, activator in blood clotting studies, and a stabilizing component of dynamite. As it is heat-resistant, it can also be used as a thermal insulator.
Other articles related to "diatomaceous earth, earth":
... Each deposit of diatomaceous earth is different, with varying blends of pure diatomaceous earth combined with other natural clays and minerals ... Many deposits throughout British Columbia, Canada, such as Red Lake Earth, are from the Miocene age and contain a species of diatom known as Melosira granulate ...
... Some filters use diatomaceous earth to help filter out contaminants ... Commonly referred to as 'D.E.' filters, they exhibit superior filtration capabilities ...
Famous quotes containing the word earth:
“On the earth the broken arcs; in the heaven a perfect round.”
—Robert Browning (18121889)