mineral
Tumbled chalcedony (likely carnelian/agate)
Microcrystalline quartz, SiO₂; chalcedony, with possible iron-oxide coloring
AI-generated identification · may be incorrectRounded 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.
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Physical properties
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.
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.
