sedimentary
Limestone
Calcium Carbonate (CaCO3)
Hardness of 3 on the Mohs scale, typically white, gray, or tan in color, dull to earthy luster, fine-grained to coarse crystalline structure, reacts strongly with dilute hydrochloric acid.
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Physical properties
Hardness of 3 on the Mohs scale, typically white, gray, or tan in color, dull to earthy luster, fine-grained to coarse crystalline structure, reacts strongly with dilute hydrochloric acid.
Formation & geological history
Formed through the accumulation of skeletal fragments from marine organisms like coral, algal, and foraminifera, as well as the chemical precipitation of calcium carbonate from water.
Uses & applications
Widely used in construction as building stone, as an aggregate for roads, as a primary component in manufacturing cement, and in agricultural soil conditioning.
Geological facts
Limestone formations often house extensive cave systems due to the solubility of calcium carbonate in slightly acidic groundwater.
Field identification & locations
Easily identified by its soft nature and characteristic fizzing reaction when exposed to acid. Commonly found in sedimentary basins worldwide.
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