mineral

Blue Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 on Mohs scale. Color: Pale blue to sky blue with white veins. 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 with white veins
Luster: Vitreous to waxy

Identified May 30, 2026More mineral →

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Physical properties

Formation & geological history

Formed through sedimentary processes, typically in marine environments as biological or chemical precipitates. It often occurs as a primary mineral in limestone and marble, forming over millions of years through the accumulation of calcium-rich debris.

Uses & applications

Used primarily for ornamental purposes, lapidary carvings, tumbled stones for the metaphysical market, and as a decorative architectural stone. In industrial forms, it is used in the production of cement and fertilizer.

Geological facts

Calcite is one of the most common minerals on Earth, but the soft blue variety is sought after by collectors; it exhibits double refraction (birefringence), meaning images viewed through a clear crystal appear doubled.

Field identification & locations

Identify in the field by its distinctive 'soapy' or waxy feel and its reaction (effervescence) to dilute hydrochloric acid. It is commonly found in large deposits in Mexico and Madagascar. Collectors look for uniform color and translucency.