mineral

Columnar Calcite / Satin Spar

Calcite (Calcium Carbonate, CaCO3)

Hardness: 3 on Mohs scale; Color: White, cream, or pale tan; Luster: Vitreous to pearly; Crystal structure: Trigonal (often appearing as fibrous or columnar aggregates); Cleavage: Perfect rhombohedral; Specific Gravity: 2.71

Hardness: 3 on Mohs scale
Color: White, cream, or pale tan
Luster: Vitreous to pearly

Identified May 28, 2026More mineral →

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Physical properties

Formation & geological history

Formed through precipitation from calcium-rich solutions in sedimentary environments, hydrothermal veins, or cave systems. This specific columnar structure often forms as flowstone or in vugs where crystals grow perpendicular to the surface.

Uses & applications

Used in the manufacture of cement and lime, as optical filters in some instruments, and as decorative specimens for collectors.

Geological facts

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

Field identification & locations

Identify in the field by its 3-direction cleavage and its immediate effervescence (fizzing) when a drop of dilute hydrochloric acid or strong vinegar is applied. Commonly found in limestone quarries and mineral veins worldwide.

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