From Simple English Wikipedia, the free encyclopedia
Ooids on the surface of an oolite limestone. Carmel Formation (Middle Jurassic) of southern Utah
Thin-section of calcitic ooids from an oolite

An ooid is a small rounded sedimentary rock. Like sand grains, ooids have a diameter of 2 mm or less. Larger grains formed the same way as ooids are called pisoids. Rock made of ooids is oolite.[1]

References[change | change source]

  1. "Ooid Sand - Sandatlas". www.sandatlas.org. Retrieved 2022-04-16.