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chalk

Definition:
A soft, pure, earthy, fine-textured, usually white to light gray or buff limestone of marine origin, consisting almost wholly (90-99%) of calcite, formed mainly by shallow-water accumulation of calcareous tests of floating microorganisms (chiefly foraminifers) and of comminuted remains of calcareous algae (such as cocoliths and rhabdoliths), set in a structureless matrix of very finely crystalline calcite. The rock is porous, somewhat friable, and only slightly coherent. It may include the remains of bottom-dwelling forms (e.g. ammonites, echinoderms, and pelecypods), and nodules of chert and pyrite. The best known and most widespread chalks are of Cretaceous age, such as those exposed in cliffs on both sides of the English Channel. (Source: BJGEO)
broader terms
non-metallic mineral
related terms
natural material
Scope note:
scope note is not available
Groups:
LITHOSPHERE (soil, geological processes)
Themes:
chemistry
materials
soil
Other relations:
Wikipedia article
Chalk
Arabic: طباشير
Basque: kreta
Bulgarian: Варовик, креда
Catalan: guix
Chinese: 白垩
Croatian: kreda
Czech: křída
Danish: kridt
Dutch: krijt
English (US): chalk
Estonian: kriit
Finnish: liitu
French: craie
German: Kreide
Greek: κιμωλία
Hungarian: kréta
Irish: cailc
Italian: gesso (minerale)
Latvian: krīts
Lithuanian: kreida
Maltese: ġibs
Norwegian: kritt (kalkstein)
Polish: kreda
Portuguese: giz
Romanian: cretă
Russian: мел
Slovak: krieda
Slovenian: kreda
Spanish: yeso
Swedish: krita
Turkish: tebeşir
Ukrainian: крейда
Concept URL: <http://www.eionet.europa.eu/gemet/concept/11207>