Orange Calcite

Physical Properties

Hardness: 3 on Mohs scale (can be scratched by a copper coin); Color: Light orange to deep amber; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Rhombohedral; Cleavage: Perfect rhombohedral in three directions; Gravity: 2.71

Formation & Geological History

Formed through sedimentary processes, often precipitated from marine environments or found as vein fillings in igneous or metamorphic rocks. It can also form in hot spring deposits as travertine. The age varies based on the host geological formation.

Uses & Applications

Used primarily for decorative objects, tumbled stones for collectors, and in the metaphysical community. In industry, calcite is a primary component of limestone and marble used in cement and soil treatment.

Geological Facts

Orange Calcite is often referred to as the 'Stone of the Mind' in lapidary circles. It is highly reactive to cold dilute hydrochloric acid, which causes it to effervesce or fizz instantly.

Field Identification & Locations

Identify in the field by its softness (3), waxy texture when tumbled, and the acid test. Look for its characteristic rhombohedral cleavage if the specimen is broken. It is commonly found in Mexico, Brazil, and parts of the USA.

Identified on: 4/13/2026

Mode: Standard