sedimentary
Chalky Limestone
Carbonate sedimentary rock (CaCO3)
Hardness: 3.0 (Mohs scale), Color: White to off-white, Luster: Dull/Earthy, Crystal Structure: Microcrystalline, Cleavage: None/Irregular
- Hardness
- 3
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Physical properties
Hardness: 3.0 (Mohs scale), Color: White to off-white, Luster: Dull/Earthy, Crystal Structure: Microcrystalline, Cleavage: None/Irregular
Formation & geological history
Formed in marine environments from the accumulation of skeletal remains of microscopic marine organisms (coccolithophores) and calcium carbonate precipitates. Typical of the Cretaceous period.
Uses & applications
Used in construction materials, cement production, agriculture for soil pH neutralization, and formerly as writing tools.
Geological facts
The White Cliffs of Dover are the most famous geological formation composed entirely of this material. It is a highly porous form of limestone.
Field identification & locations
Identified by its white color, powdery texture, and strong effervescence (bubbles) when a drop of cold dilute hydrochloric acid is applied. Commonly found in coastal areas and quarries.
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