mineral

Blue Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 on Mohs scale; Color: Pale blue to sky blue; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Rhombohedral; Cleavage: Perfect rhombohedral in three directions; Specific Gravity: 2.71

Hardness: 3 on Mohs scale
Color: Pale blue to sky blue
Luster: Vitreous to waxy

Identified April 13, 2026More mineral →

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Physical properties

Hardness: 3 on Mohs scale; Color: Pale blue to sky blue; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Rhombohedral; Cleavage: Perfect rhombohedral in three directions; Specific Gravity: 2.71

Formation & geological history

Formed through sedimentary processes or as a secondary mineral in igneous and metamorphic rocks. It often precipitates from marine environments or hydrothermal veins. This specimen shows the typical mass form common in sedimentary limestone-rich regions.

Uses & applications

Primarily used for ornamental carvings, decorative stones, and as a popular specimen for crystal healing and mineral collectors. In industry, calcite is used for cement, local building stone, and acid neutralization.

Geological facts

Calcite is one of the most common minerals on Earth. The blue variety gets its color from the inclusion of specific impurities or light scattering caused by microscopic inclusions within the crystal lattice.

Field identification & locations

Identify in the field by its softness (can be scratched by a copper coin) and its effervescence (bubbling) when in contact with weak acids like vinegar. It also features a distinctive 'greasy' or waxy feel when polished.