Diatomaceous Earth
“A rock made of tiny glass fossils”
Diatomaceous earth is an extremely lightweight, porous sedimentary rock composed of the silica skeletons of diatoms — microscopic single-celled algae. Each grain contains intricate, perforated structures visible only under a microscope, giving the material remarkable filtering and absorbent properties.
amorphous silica (opal-A), diatom frustules, clay minerals (minor), volcanic ash (minor)
Lompoc (California, USA), Denmark, Kenya, China, Kieselguhr deposits (Germany), Iceland
1-1.5 (crumbly)
Alfred Nobel's invention of dynamite was made possible by diatomaceous earth — he discovered that soaking nitroglycerin into this porous rock made the explosive safe to handle and transport.
Test Your Knowledge
Why is diatomaceous earth an effective natural insecticide despite being non-toxic to mammals?
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