mineral

Aragonite (Yellow/Honey Tumble)

Calcium Carbonate (CaCO3)

Hardness: 3.5-4 (Mohs scale); Color: Pale yellow to honey gold; Luster: Vitreous to resinous; Crystal structure: Orthorhombic; Cleavage: Distinct in one direction; Specific gravity: 2.95

Hardness: 3
Color: Pale yellow to honey gold
Luster: Vitreous to resinous

Identified March 14, 2026More mineral →

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Physical properties

Hardness: 3.5-4 (Mohs scale); Color: Pale yellow to honey gold; Luster: Vitreous to resinous; Crystal structure: Orthorhombic; Cleavage: Distinct in one direction; Specific gravity: 2.95

Formation & geological history

Formed through low-temperature biological and physical processes, including precipitation in marine and freshwater environments. It is a more chemically unstable polymorph of calcium carbonate compared to calcite and often originates in caves as speleothems or in shells of marine organisms.

Uses & applications

Primarily used as a collector specimen or decorative tumbled stone. In industry, aragonite is used in cement, livestock feed, and for neutralizing soil acidity. Large deposits are mined for use in glass manufacturing.

Geological facts

Aragonite is the primary component of pearls and mother-of-pearl (nacre). Despite having the same chemical formula as calcite, its atoms are arranged differently, making it harder and more dense. It will dissolve and fizz vigorously if exposed to weak acids like vinegar.

Field identification & locations

Identify in the field by its high luster and reactivity to acid. It is commonly found in Morocco, Spain (where it was first discovered in the Aragon region), and Namibia. This specimen is a 'tumbled' version, meaning it has been mechanically polished to remove rough edges.

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