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 1, 2026More mineral →

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Physical properties

Formation & geological history

Formed through sedimentary processes or as a secondary mineral in igneous and metamorphic rocks. It often precipitates from marine organisms or in hydrothermal veins and caves.

Uses & applications

Primarily used for lapidary purposes (ornamental carvings and spheres), crystal healing/metaphysical collecting, and as a calcium source in chemical industries.

Geological facts

Blue calcite is one of the most common varieties of calcite found in large masses. Its distinctive blue color is often attributed to tiny inclusions of other minerals or structural defects caused by trace elements.

Field identification & locations

Identify in the field by its softness (can be scratched by a copper coin) and its effervescence (fizzing) when exposed to cold dilute hydrochloric acid. Commonly found in large deposits in Madagascar and Mexico.