sedimentary
Stalagmite (Flowstone)
Speleothem (Calcium Carbonate, CaCO3)
Hardness: 3 (Mohs scale), Color: Creamy white to brownish due to impurities, Luster: Vitreous to pearly, Crystal structure: Trigonal (Calcite), Cleavage: Perfect rhombohedral
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Physical properties
Hardness: 3 (Mohs scale), Color: Creamy white to brownish due to impurities, Luster: Vitreous to pearly, Crystal structure: Trigonal (Calcite), Cleavage: Perfect rhombohedral
Formation & geological history
Formed over thousands of years by the precipitation of minerals from water dripping in caves. The mineral-rich water deposits layers of calcium carbonate as it evaporates.
Uses & applications
Primarily used as decorative display pieces, museum specimens, or for scientific research on paleoclimates.
Geological facts
The growth rate of stalagmites is incredibly slow, often averaging 0.007 to 0.5 mm per year. They are essentially time capsules that record ancient climate changes.
Field identification & locations
Identify by its conical or mound-like shape with distinct horizontal layering (growth rings). Common in limestone cavern systems worldwide. Removal from natural caves is often illegal.
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