Orange Calcite (Banded Calcite)

Physical Properties

Hardness: 3 on Mohs scale (can be scratched by a copper penny); Color: Orange, yellow, cream with horizontal banding; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: Perfect rhombohedral; Specific Gravity: 2.71

Formation & Geological History

Formed through sedimentary processes, primarily in marine environments where calcium carbonate precipitates out of water. Often found in massive forms or as vein fillings.

Uses & Applications

Used primarily as decorative stones, in lapidary work for carvings or polished points, and as mineral specimens for collectors. In industry, calcite is used in the manufacture of cement and lime.

Geological Facts

Calcite is one of the most common minerals on Earth. It is the primary component of limestone and marble. Orange calcite specifically is sensitive to acids and will effervesce (fizz) if exposed to diluted hydrochloric acid or vinegar.

Field Identification & Locations

Identify by its relative softness (easily scratched) and its waxy luster when polished. It often exhibits distinctive horizontal banding from varying mineral impurity levels during growth. Commonly sourced from Mexico.

Identified on: 5/9/2026

Mode: Standard