mineral

Agate

Silicon Dioxide (SiO2)

Hardness: 6.5-7 on Mohs scale. Color: Brown, tan, white, and translucent; display waxy to vitreous luster. Crystal structure: Hexagonal (cryptocrystalline). Cleavage: None, exhibits conchoidal fracture.

Hardness: 6
Color: Brown, tan, white, and translucent

Identified June 19, 2026More mineral →

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Physical properties

Formation & geological history

Formed as a secondary mineral in volcanic cavities or sedimentary rocks through the deposition of silica-rich groundwater. Usually found in nodes or geodes.

Uses & applications

Used in gemstone jewelry, ornamental carvings, tumbled decorative stones, and industrially for precision pendulums or laboratory mortars and pestles because of its hardness.

Geological facts

Agate is named after the Achates River in Sicily where it was first discovered. Every agate is unique because their band patterns and colors are determined by specific mineral impurities during formation.

Field identification & locations

Identify in the field by its translucency (hold to light), characteristic waxy texture, and bands. Commonly found in river beds, beaches, and areas with ancient volcanic activity.