Pisolite

{{short description|Sedimentary rock made of large grains, usually of calcium carbonate}}

Image:PisolitesConococheagueUpperCambrian.jpg

Image:Calcario2EZ.jpg, Rio de Janeiro, Brazil; pisolith diameters average 1.0 cm]]

Image:Qemscan_pisoliths.png mineral map of bauxite forming pisoids]]

A pisolite ({{ety|grc|πίσον (píson)|pea}}) is a sedimentary rock made of pisoids, which are concretionary grains – typically of calcium carbonate which resemble ooids, but are more than 2 mm in diameter.[http://www.mindat.org/min-26778.html Mindat - Pisolite] These grains are approximately spherical and have concentric layers reaching 10 mm in diameter.

Bauxites, limonites, and siderites often have a pisolitic structure.