mineral

Blue Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 on Mohs scale. Color: Pale blue to sky blue. Luster: Vitreous to waxy. Crystal system: 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 23, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in sedimentary environments through chemical precipitation or by the accumulation of shell, coral, and algal debris. It can also form in hydrothermal veins or as a secondary mineral in igneous and metamorphic rocks.

Uses & applications

Mostly used for ornamental purposes, decorative carvings, lapidary work, and as a popular specimen for mineral collectors and metaphysical practitioners.

Geological facts

Calcite is one of the most common minerals on Earth. The blue variety specifically gets its color from light-dispersing inclusions or natural irradiation. It can produce a double refraction effect known as 'Iceland Spar' in clear specimens.

Field identification & locations

Identify by its light blue color, waxy feel, and rhombohedral cleavage planes. It will vigorously effervesce (fizz) when exposed to a drop of dilute hydrochloric acid. Commonly found in Mexico, South Africa, and Madagascar.