sedimentary
Limestone
Calcium Carbonate (CaCO3)
Hardness of 3 on the Mohs scale, colors range from white, gray, tan, to yellow, dull to metallic luster, crystal structure is usually fine-grained or microcrystalline, specific gravity is 2.7.
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Physical properties
Hardness of 3 on the Mohs scale, colors range from white, gray, tan, to yellow, dull to metallic luster, crystal structure is usually fine-grained or microcrystalline, specific gravity is 2.7.
Formation & geological history
Formed through the accumulation and compaction of organic remains such as shells, coral, and algal debris in shallow marine environments over millions of years.
Uses & applications
Widely used in the construction industry for making cement, crushed stone for road bases, as a building material, and in agriculture to neutralize soil acidity.
Geological facts
Limestone often contains fossils of ancient marine organisms and forms spectacular cave systems through dissolution by acidic groundwater.
Field identification & locations
Can be easily identified in the field by its characteristic fizzing or effervescence when a drop of weak hydrochloric acid or vinegar is applied.
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