sedimentary
Tumbled Agate
Silicon Dioxide (SiO2)
Hardness of 6.5 to 7 on the Mohs scale, colors vary widely including grey, white, brown, and blue, waxy to vitreous luster, microcrystalline quartz structure with conchoidal fracture.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, colors vary widely including grey, white, brown, and blue, waxy to vitreous luster, microcrystalline quartz structure with conchoidal fracture.
Formation & geological history
Formed in cavities of ancient volcanic and metamorphic rocks through the deposition of silica from groundwater circulating over millions of years.
Uses & applications
Commonly used in ornamental jewelry, tumbled stones for collection, decorative items, and lapidary art.
Geological facts
Agate is a variety of chalcedony. The name comes from the Achates River in Sicily, where stones were found in ancient times.
Field identification & locations
Easily identified by its hardness, smooth polished texture when tumbled, and faint banding patterns visible under light. Found worldwide.
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