Yellow Calcite

Physical Properties

Hardness: 3 on Mohs scale; Color: Pale yellow to deep honey; Luster: Vitreous to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: Perfect rhombohedral; Specific Gravity: 2.71

Formation & Geological History

Formed through sedimentary precipitation in marine environments or hydrothermal veins. It can also occur in metamorphic or igneous settings as a secondary mineral.

Uses & Applications

Used in the production of cement and mortar, as a soil conditioner in agriculture, in the optical industry (Iceland Spar), and as decorative stones or tumbled pocket stones in collecting.

Geological Facts

Calcite is one of the most common minerals on Earth. It exhibits double refraction, where an image seen through a clear crystal appears doubled.

Field Identification & Locations

Identify in the field by its 3-way rhombohedral cleavage and its strong reaction (fizzing) to dilute hydrochloric acid. It is much softer than quartz and can be scratched by a copper coin.

Identified on: 4/21/2026

Mode: Standard