mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 (Mohs scale), Color: Orange to peach-pink, Luster: Vitreous to waxy, Crystal Structure: Trigonal/Rhombohedral, Cleavage: Perfect rhombohedral in three directions, Specific Gravity: 2.71

Identified June 18, 2026More mineral →

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Physical properties

Hardness: 3 (Mohs scale), Color: Orange to peach-pink, Luster: Vitreous to waxy, Crystal Structure: Trigonal/Rhombohedral, Cleavage: Perfect rhombohedral in three directions, Specific Gravity: 2.71

Formation & geological history

Formed through sedimentary processes such as chemical precipitation in marine environments, or in hydrothermal veins and hot springs. It can occur in any geological age but is foundational in limestone and marble formations.

Uses & applications

Used in the manufacturing of cement and lime, as a soil conditioner in agriculture, for optical instruments when clear (Iceland Spar), and highly popular for decorative carving, jewelry, and metaphysical collections.

Geological facts

Calcite is one of the most common minerals on Earth. It is famous for its double refraction (birefringence) and its ability to effervesce or fizz when in contact with even weak acids like vinegar.

Field identification & locations

Identify in the field by its rhombohedral cleavage (tilting blocks), its softness (scratched by a copper penny but not a fingernail), and the acid test. Commonly found in Mexico, Brazil, and the USA.