mineral

Blue Calcite

Calcium Carbonate (CaCO3)

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

Identified June 13, 2026More mineral →

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Physical properties

Formation & geological history

Formed through sedimentary processes, often as a chemical precipitate from calcium-rich waters or in hydrothermal veins. It is a major component of limestone and marble, found globally in various geological ages.

Uses & applications

Used primarily as decorative carvings, tumbled stones, and in the metaphysical/healing crystal industry. Industrial calcite is used in cement, antacids, and as a soil conditioner.

Geological facts

Blue Calcite is known for its soft, soothing color which is often caused by the inclusion of minute amounts of other minerals during formation. It is one of the most common minerals on Earth in its clear form, but the blue variety is highly sought after by collectors.

Field identification & locations

Can be identified in the field by its softness (can be scratched by a copper penny) and its vigorous reaction (effervescence) when touched with room-temperature dilute hydrochloric acid. Commonly found in large deposits in Mexico and Madagascar.