mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 on Mohs scale; Color: Pale to deep orange/honey; Luster: Vitreous to waxy; Crystal structure: Trigonal/Rhombohedral; Cleavage: Perfect rhombohedral; Specific Gravity: 2.71

Hardness: 3 on Mohs scale
Color: Pale to deep orange/honey
Luster: Vitreous to waxy

Identified April 5, 2026More mineral →

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Physical properties

Hardness: 3 on Mohs scale; Color: Pale to deep orange/honey; Luster: Vitreous to waxy; Crystal structure: Trigonal/Rhombohedral; Cleavage: Perfect rhombohedral; Specific Gravity: 2.71

Formation & geological history

Formed through sedimentary processes, often in marine environments via chemical precipitation or biological activity. It can also form in hydrothermal veins or as a secondary mineral in igneous rocks.

Uses & applications

Used in the manufacturing of cement and mortar, as a soil conditioner in agriculture, in the optical industry (high-quality clear specimens), and extensively in the gemstone and metaphysical decor market.

Geological facts

Orange calcite is known for its 'acid test' reaction; it will effervesce (fizz) vigorously when it comes into contact with dilute hydrochloric acid. It is one of the most common minerals on Earth's surface.

Field identification & locations

Identify by its waxy texture, rhombohedral cleavage, and the fact that it can be scratched by a copper coin but not by a fingernail. Found globally, with notable deposits in Mexico, Brazil, and the USA.