mineral

Yellow Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 (Mohs scale), Color: light yellow to deep orange/golden, Luster: Vitreous to waxy, Crystal structure: Trigonal/Rhombohedral, Cleavage: Perfect rhombohedral in three directions, Specific gravity: 2.71

Identified June 3, 2026More mineral →

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Physical properties

Formation & geological history

Formed through sedimentary processes, chemical precipitation in caves, or as a byproduct of hydrothermal activity. It is common in limestone and marble environments across all geological eras.

Uses & applications

Used in the manufacture of cement, lime for soil treatment, as a pigment, in acid neutralization, and widely as a decorative stone or 'healing' crystal in the New Age community.

Geological facts

Calcite is the most common form of calcium carbonate and is known for its property of double refraction, where light entering the crystal is split into two rays. It reacts instantly with weak acids like vinegar by fizzing.

Field identification & locations

Identified in the field by its 3-way rhombohedral cleavage, its softness (can be scratched by a copper coin), and its effervescence with HCl. Commonly found in Mexico, Brazil, and the USA.