mineral

Blue Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 on Mohs scale; Color: Powdery sky blue to pale blue; Luster: Vitreous to waxy/pearly; Crystal System: Trigonal; Cleavage: Perfect rhombohedral; Specific Gravity: 2.71

Hardness: 3 on Mohs scale
Color: Powdery sky blue to pale blue
Luster: Vitreous to waxy/pearly

Identified July 18, 2026More mineral →

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Physical properties

Hardness: 3 on Mohs scale; Color: Powdery sky blue to pale blue; Luster: Vitreous to waxy/pearly; Crystal System: Trigonal; Cleavage: Perfect rhombohedral; 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 calcium-rich hydrothermal fluids or in marine environments.

Uses & applications

Primarily used as a decorative stone, lapidary material for carvings and cabochons, and a popular specimen for mineral collectors and metaphysical practitioners.

Geological facts

Calcite is one of the most common minerals on Earth, but the distinct soft blue variety is more localized. It is known for its double refraction property, where light splitting through a clear crystal creates a double image.

Field identification & locations

Identify by its characteristic 'soapy' or waxy feel and its softness (it can be scratched by a copper penny). It will also effervesce (fizz) when in contact with weak hydrochloric acid or vinegar. Common sources include Mexico, Madagascar, and Brazil.