mineral

Tumbled chalcedony (likely carnelian/agate)

Microcrystalline quartz, SiO₂; chalcedony, with possible iron-oxide coloring

AI-generated identification · may be incorrect

Rounded and polished, translucent brown-orange with pale internal banding and a waxy to glassy luster. Quartz hardness is about 7 Mohs; no obvious cleavage, conchoidal fracture, and specific gravity around 2.6.

Identified August 9, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater fills cavities and fractures, precipitating fibrous quartz; iron oxides create the orange-brown color. The smooth shape indicates human tumbling and polishing, so its original geological age cannot be determined.

Uses & applications

Used for cabochons, beads, carvings, ornaments, and lapidary specimens; common pieces have modest jewelry and collecting value.

Geological facts

The specimen may be called carnelian if the orange-red portion is dominant, or agate if distinct curved banding is confirmed. Surface translucency and internal bands distinguish it from ordinary opaque brown stone.

Field identification & locations

Likely identifiable by its hardness, translucent edges, waxy luster, and curved quartz banding. Chalcedony and agate are common in volcanic terrains, including the Ecuadorian Andes near the reported location; a precise locality cannot be inferred from this photograph.