Diatom

About it

Microscopic algae with glassy silica shells, round or boat-shaped and finely patterned. A microscope is needed to see single ones; they pile up as diatomite, mined at Lompoc, California.

Type

Fossil (microfossil)

Group

Diatom (alga)

Colours

white, cream, pale grey

Transparency

opaque

Periods

Cretaceous, Paleogene, Neogene, Quaternary

Typical values: real specimens vary. For more, see mindat.org.