Diatomite

Diatomite properties at a glance

Geology & background

Forms from accumulations of microscopic diatom shells in lakes or marine basins that later compact into soft silica-rich rock.

Diatomite deposits record ancient productive lakes and marine environments.

How to identify Diatomite

• Look for a very light, soft, chalky rock.
• Diatomite may be white, cream, tan, or pale gray.
• It can feel porous or absorbent compared with limestone.
• Avoid breathing dust from powdered or crumbly material.

Where Diatomite is found

Diatomite occurs in many sedimentary settings worldwide; exact locality should be verified from field notes, maps, or specimen provenance.

How much is Diatomite worth?

Diatomite is usually valued for teaching, field context, locality, texture, fossils, color, or unusual structures rather than high gem value.

Common uses

• Filtration
• Absorbents
• Abrasives
• Education
• Field identification

Interesting facts

• Diatomite is also called diatomaceous earth when loose or powdered.
• It can feel unusually lightweight and absorbent.
• The tiny diatom skeletons are usually only visible under magnification.

Care & safety

Diatomite can be soft, porous, crumbly, or weakly cemented depending on grain size, cement, and weathering.

Avoid inhaling dust. Do not cut, grind, or polish unknown sedimentary rocks without eye protection and a properly rated respirator.

Related rocks & minerals

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