Rock Identifier
Aragonite cluster (blue aragonite, likely copper-associated) (Aragonite, orthorhombic CaCO₃; blue color may reflect copper minerals or treatment) — mineral
mineral

Aragonite cluster (blue aragonite, likely copper-associated)

Aragonite, orthorhombic CaCO₃; blue color may reflect copper minerals or treatment

AI-generated identification · may be incorrect

Hardness 3.5–4 Mohs; pale turquoise-blue, vitreous to pearly luster, commonly radiating/prismatic crystals, uneven cleavage, specific gravity about 2.94. The matrix appears dark, granular, and possibly copper-mineralized.

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Physical properties

Hardness 3.5–4 Mohs; pale turquoise-blue, vitreous to pearly luster, commonly radiating/prismatic crystals, uneven cleavage, specific gravity about 2.94. The matrix appears dark, granular, and possibly copper-mineralized.

Formation & geological history

Forms in low-temperature hydrothermal cavities, caves, hot-spring deposits, and oxidized copper-ore zones; the specimen likely formed in a relatively young secondary mineral environment, though exact age and locality require provenance.

Uses & applications

Primarily a collector specimen; aragonite is also used scientifically and occasionally as a minor carbonate raw material, but this delicate crystal cluster is unsuitable for construction or jewelry wear.

Geological facts

Aragonite is polymorphous with calcite: both are CaCO₃ but have different crystal structures. Blue aragonite is uncommon, and vivid color can be enhanced by copper staining, coatings, or dyes.

Field identification & locations

Identify by its radiating needle-like crystals, softness, and reaction with dilute hydrochloric acid or vinegar; avoid prolonged acid or water exposure. Common localities include Morocco, Spain, Mexico, Namibia, and copper districts worldwide.