mineral

Polished carnelian-rich agate (likely polyhedral jasper/chalcedony)

Microcrystalline quartz, SiO₂, with iron-oxide inclusions

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; waxy to glassy luster, translucent orange-brown, red, gray, and black areas, with conchoidal fracture and no cleavage. The glossy surface appears polished or wet, and the irregular shape may be natural or deliberately shaped.

Identified August 10, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater fills cavities in volcanic rock, depositing chalcedony and iron oxides in layers or patches. Agate formation commonly occurred from the Precambrian through Cenozoic eras, depending on locality.

Uses & applications

Used for cabochons, carvings, beads, ornaments, and lapidary specimens; too small or irregular for typical construction use.

Geological facts

Orange-red coloration generally comes from hematite or goethite. Strong banding, translucency, and ability to scratch glass support an agate/chalcedony identification.

Field identification & locations

Common in volcanic terrains worldwide, including Brazil, Uruguay, India, Madagascar, Mexico, and the western United States. Inspect edges for translucency and banding; distinguish it from glass by its natural inclusions, hardness, and cooler stone feel.