mineral

Tumbled blue stone, likely blue calcite or dyed stone

Probably calcite (CaCO₃); exact identification is uncertain from the blurred image

AI-generated identification · may be incorrect

Pale blue, opaque to translucent, matte-to-waxy luster, rounded and polished with flat faces. Calcite has Mohs hardness 3, rhombohedral cleavage, and specific gravity about 2.7; blue color may also indicate dyed quartz, aragonite, or larimar.

Identified September 20, 2026More mineral →

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Physical properties

Formation & geological history

Natural blue calcite forms in sedimentary or hydrothermal deposits through precipitation of calcium carbonate; geological ages vary widely. The specimen appears human-shaped or tumbled, so its present surface is workshop-made.

Uses & applications

Used mainly as a decorative or collecting stone; not generally suitable for durable jewelry because calcite scratches easily. Blue calcite specimens are also sold for lapidary and ornamental use.

Geological facts

Calcite effervesces visibly in dilute hydrochloric acid or strong vinegar, though polished surfaces may react slowly. The image is insufficient to distinguish calcite from other blue stones confidently.

Field identification & locations

Check hardness with a steel knife or copper coin, cleavage, acid reaction, and streak; avoid scratching valuable surfaces. Blue calcite is common in Mexico, Madagascar, Brazil, and the United States; larimar is restricted mainly to the Dominican Republic.