mineral

Agate

SiO2 (Silicon dioxide, cryptocrystalline quartz)

AI-generated identification · may be incorrect

Hardness: 6.5-7, Color: Gray, white, translucent with varied inclusions (possibly an ocean agate or similar variety), Luster: Vitreous, Crystal structure: Trigonal (microcrystalline), Cleavage: None

Hardness: 6

Identified June 18, 2026More mineral →

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Physical properties

Hardness: 6.5-7, Color: Gray, white, translucent with varied inclusions (possibly an ocean agate or similar variety), Luster: Vitreous, Crystal structure: Trigonal (microcrystalline), Cleavage: None

Formation & geological history

Forms in cavities of volcanic rocks or ancient lavas, where silica-rich waters deposit microcrystalline quartz in concentric layers.

Uses & applications

Lapidary art, jewelry, ornamental carvings, collecting.

Geological facts

Agate is a diverse type of chalcedony characterized by its fineness of grain and brightness of color. It is named after the Achates River in Sicily where it was first found.

Field identification & locations

Identifiable by its smooth polish, waxy or vitreous luster, banded or translucent appearance with distinct inclusions. Commonly found worldwide in areas with past volcanic activity.