mineral

Tumbled chalcedony (likely carnelian/agate)

Microcrystalline quartz, SiO₂; iron-oxide-bearing chalcedony

AI-generated identification · may be incorrect

Hardness 6.5–7 Mohs; translucent cream, honey-brown, and reddish-brown zones with a waxy to vitreous luster. Massive, cryptocrystalline quartz with no visible cleavage and conchoidal fracture; polishing indicates a tumbled specimen.

Identified August 23, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater fills cavities and fractures in volcanic rocks, with iron oxides producing the yellow-red coloration. Chalcedony deposits range from Paleozoic to recent, depending on locality.

Uses & applications

Used for beads, cabochons, carvings, and ornamental objects; common polished specimens generally have modest value.

Geological facts

The specimen may be marketed as yellow carnelian, honey agate, or brecciated chalcedony, though precise naming requires closer inspection or testing.

Field identification & locations

Identify by its fine texture, translucency, waxy luster, strong polish, and hardness; it should resist scratching by a steel blade. Common sources include Brazil, Uruguay, India, Madagascar, and the United States.