mineral

White Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 on Mohs scale (can be scratched by a copper coin); Color: White to colorless; Luster: Vitreous to pearly; Crystal structure: Trigonal/Hexagonal; Cleavage: Perfect rhombohedral in three directions; Specific gravity: 2.71.

Hardness: 3 on Mohs scale (can be scratched by a copper coin)
Color: White to colorless
Luster: Vitreous to pearly

Identified April 22, 2026More mineral →

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Physical properties

Formation & geological history

Formed through sedimentary processes like chemical precipitation in marine environments, or as a primary mineral in igneous and metamorphic rocks (such as marble). It is one of the most common minerals on Earth's crust.

Uses & applications

Used in the manufacturing of cement and mortar, as a soil conditioner in agriculture, a pigment in paint, and for pharmaceutical purposes (antacids). Tumbled stones are popular in the metaphysical and jewelry trade.

Geological facts

Calcite exhibits double refraction; if you place a clear crystal over a line, it will appear as two lines. It is the primary component of limestone and marble.

Field identification & locations

Identify in the field using the 'acid test'—it will effervesce (fizz) vigorously when touched with dilute hydrochloric acid or strong vinegar. It is very soft compared to quartz.