mineral

Blue Calcite

Calcium Carbonate (CaCO3)

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

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

Identified June 3, 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; Cleavage: Perfect rhombohedral; Specific Gravity: 2.71

Formation & geological history

Formed through sedimentary processes or in hydrothermal veins where calcium-rich fluids precipitate. It is most commonly found in massive form rather than distinct crystals in this blue variety.

Uses & applications

Used primarily for ornamental purposes, lapidary carvings, decorative stones, and by collectors. In industrial forms (as limestone), it is used in cement and agriculture.

Geological facts

Blue Calcite is often associated with soothing properties in metaphysical circles. It reacts and fizzes when in contact with weak acids like vinegar, which is a classic test for carbonates.

Field identification & locations

Identify in the field by its soft hardness (can be scratched by a copper penny) and its rhombohedral cleavage. Notable deposits are found in Mexico, Africa, and Brazil.