mineral

Orange Calcite (Cleavage Rhomb)

Calcite (Calcium Carbonate, CaCO3)

Hardness: 3 on Mohs scale; Color: Orange/Honey; Luster: Vitreous to waxy; Crystal Structure: Trigonal (often found as rhombohedral cleavage fragments); Cleavage: Perfect rhombohedral in 3 directions; Specific Gravity: 2.71

Hardness: 3 on Mohs scale
Color: Orange/Honey
Luster: Vitreous to waxy

Identified April 18, 2026More mineral →

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Physical properties

Formation & geological history

Formed through sedimentary processes, chemical precipitation in marine environments, or hydrothermal veins. This specimen likely formed in a sedimentary or hydrothermal environment and was later shaped into a cube or cleaved naturally into a rhomb.

Uses & applications

Used as a decorative stone, in crystal healing/spiritual practices, as a source for lime in cement, and in the chemical industry.

Geological facts

Calcite exhibits double refraction (birefringence), where light passing through a clear specimen splits into two rays. It is the primary component of limestone and marble.

Field identification & locations

Identify by its 3-way rhombohedral cleavage and its rapid effervescence (fizzing) when exposed to a drop of cold, dilute hydrochloric acid. It is found globally, with famous deposits in Mexico, Brazil, and the USA.

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