mineral

Blue Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 on Mohs scale; Color: Powdery light blue to sky blue; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Rhombohedral; Cleavage: Perfect rhombohedral in three directions; Specific Gravity: 2.71

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

Identified March 14, 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. Large deposits are frequently found in Mexico and Madagascar, typically dating from various geological periods depending on the host rock.

Uses & applications

Primarily used for ornamental purposes, lapidary carvings, and as a popular specimen for mineral collectors. In industry, calcite is used in the manufacture of cement, lime, and as a neutralizing agent in the chemical industry.

Geological facts

Blue Calcite is known for its 'waxy' texture when handled. It is chemically identical to clear Iceland Spar and marble, but trace elements or structural imperfections during formation give it its distinct blue hue. It will effervesce (bubble) if a drop of weak acid like vinegar is applied.

Field identification & locations

Identify in the field by its rhombohedral cleavage planes, softness (can be scratched by a copper penny), and its characteristic waxy luster. Common locations include Chihuahua, Mexico and various regions in Madagascar and Brazil.