mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 on Mohs scale; Color: Honey-orange to golden; Luster: Vitreous to waxy; Crystal structure: Trigonal/Rhombohedral; Cleavage: Perfect rhombohedral in three directions; Specific gravity: 2.71

Hardness: 3 on Mohs scale
Color: Honey-orange to golden
Luster: Vitreous to waxy

Identified March 15, 2026More mineral →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Formed through sedimentary processes, often precipitated from marine environments or within caves. It can also form through hydrothermal activity. While calcite exists throughout geological history, many high-quality orange specimens are sourced from modern-day deposits.

Uses & applications

Used primarily for decorative carvings, lapidary work (cabs and spheres), and as a metaphysical/healing stone in the gift shop industry. In bulk, calcite is used as a flux in metallurgy and in the production of cement.

Geological facts

Orange calcite is often called the 'stone of the mind' by collectors. It is highly reactive to cold dilute hydrochloric acid, which will cause it to effervesce (fizz) immediately due to its carbonate composition.

Field identification & locations

Identify in the field by its distinctive waxy texture and rhombohedral cleavage. It can be scratched by a copper penny but not by a fingernail. Found commonly in Mexico, Brazil, and parts of the USA (like Utah). Use an acid test (vinegar or lemon juice) for a mild reaction as a confirmation.