mineral

Aragonite

Aragonite (CaCO3)

Hardness: 3.5 to 4 on Mohs scale. Color: Typically white, reddish-brown, yellow, or gray. Luster: Vitreous to resinous. Crystal structure: Orthorhombic, often forming pseudo-hexagonal prismatic crystals, columnar clusters, or spiky 'flos-ferri' formations. Cleavage: Distinct in one direction. Specific gravity: 2.93.

Hardness: 3
Color: Typically white, reddish-brown, yellow, or gray
Luster: Vitreous to resinous

Identified August 5, 2026More mineral →

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Physical properties

Formation & geological history

Forms in low-temperature environments, including marine deposits, hot spring precipitates, caves (as stalactites or flowstone), and altered limestone beds.

Uses & applications

Used primarily as a mineral specimen for collectors, in metaphysical practices, and occasionally in agricultural lime or soil conditioning.

Geological facts

Aragonite is a polymorph of calcite, meaning it shares the exact same chemical formula (calcium carbonate) but has a different crystal structure, making it less stable than calcite over geological time.

Field identification & locations

Easily identified by its characteristic pseudo-hexagonal prismatic crystal clusters, brownish-pink color, and effervescence when tested with dilute hydrochloric acid. Commonly found in Tazouta, Morocco, and various locations in Spain and the USA.