gemstone

Tumbled Agate

Silicon Dioxide (Chalcedony variety), SiO2

Hardness: 6.5-7 on the Mohs scale, Color: Various shades of grey, brown, white, or translucent, Luster: Vitreous to waxy, Crystal Structure: Trigonal (microcrystalline/cryptocrystalline), Cleavage: None, Specific Gravity: 2.58-2.64

Hardness: 6

Identified August 3, 2026More gemstone →

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Physical properties

Formation & geological history

Formed by the deposition of silica from groundwater, typically in cavities of igneous and sedimentary rocks, over millions of years.

Uses & applications

Used in jewelry, ornamental carvings, polished display stones, and metaphysical healing.

Geological facts

Agate has been used since ancient times for decorative items, seals, and talismans, and is named after the Achates River in Sicily where it was first found.

Field identification & locations

Can be identified by its conchoidal fracture, waxy luster, and smooth tumbled finish. Found worldwide in regions with volcanic activity or silica-rich deposits.

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