Orange Calcite (Cleavage Rhomb)

Physical Properties

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

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.

Identified on: 4/18/2026

Mode: Standard