mineral
Calcite
Calcium Carbonate (CaCO3)
Hardness: 3 on Mohs scale; Color: Tan, beige, or colorless; Luster: Vitreous to pearly; Crystal structure: Trigonal/Rhombohedral; Cleavage: Perfect rhombohedral in three directions; Specific Gravity: 2.71
- Hardness
- 3 on Mohs scale
- Color
- Tan, beige, or colorless
- Luster
- Vitreous to pearly
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Physical properties
Hardness: 3 on Mohs scale; Color: Tan, beige, or colorless; Luster: Vitreous to pearly; Crystal structure: Trigonal/Rhombohedral; Cleavage: Perfect rhombohedral in three directions; Specific Gravity: 2.71
Formation & geological history
Formed through sedimentary processes, often precipitated from marine environments or hydrothermal veins. It is most commonly found in limestone and marble formations across many geological ages.
Uses & applications
Used as a flux in steel manufacturing, as a soil conditioner in agriculture, in the production of cement, and as a popular mineral specimen for collectors.
Geological facts
Calcite exhibits double refraction when clear, meaning an image viewed through it appears doubled. It is the primary component of stalactites and stalagmites in caves.
Field identification & locations
Identify in the field by its rhombohedral cleavage and its strong effervescence when exposed to cold dilute hydrochloric acid. It is commonly found in sedimentary basins and limestone caverns.
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Schist
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Potassium Feldspar (Orthoclase)
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Mineral
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
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