sedimentary
Chalk
Micritic limestone (CaCO3)
AI-generated identification · may be incorrectHardness 1 on Mohs scale, white or light gray color, earthy luster, microcrystalline structure, specific gravity 1.9-2.7.
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Physical properties
Hardness 1 on Mohs scale, white or light gray color, earthy luster, microcrystalline structure, specific gravity 1.9-2.7.
Formation & geological history
Formed from the accumulation of microscopic calcite shells (coccoliths) of marine microalgae over millions of years.
Uses & applications
Used in agriculture for soil neutralization, manufacturing of lime, blackboard chalk, and various industrial applications.
Geological facts
Famous chalk deposits include the White Cliffs of Dover, formed during the Cretaceous period.
Field identification & locations
Identified by its soft, powdery texture and effervescence when treated with dilute hydrochloric acid.
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