mineral

Orange calcite (likely rough specimen)

Calcite, calcium carbonate (CaCO₃)

AI-generated identification · may be incorrect

Usually Mohs hardness 3, vitreous to pearly luster, orange to cream coloration, and prominent rhombohedral cleavage; the irregular texture may reflect weathering or matrix. Crystal structure is trigonal. Exact identification is uncertain from an image alone.

Identified August 20, 2026More mineral →

Explore Orange calcite (likely rough specimen) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Forms when calcium-rich groundwater or hydrothermal fluids precipitate carbonate, and commonly occurs in limestone cavities, veins, and sedimentary deposits. Orange color can result from iron or other trace impurities; age depends on the host deposit.

Uses & applications

Used in cement, lime, aggregate, soil treatment, and as a collectible or decorative mineral; translucent orange material may be cut or polished, though this piece appears low-grade.

Geological facts

Calcite effervesces vigorously with dilute hydrochloric acid or vinegar, though vinegar may react slowly. It is much softer than quartz and can be scratched with a steel knife.

Field identification & locations

Common worldwide, including Mexico, the United States, Brazil, and Peru. Confirm with a hardness test and acid reaction; similar orange aragonite or weathered limestone are possible.