mineral
Weathered quartz-rich pebble, possibly jasper or chert
Microcrystalline quartz (SiO₂), with iron-oxide staining and possible clay/mineral inclusions
AI-generated identification · may be incorrectHardness about 6.5–7 Mohs; tan, brown, gray, and reddish coloration; dull to waxy luster; massive, non-cleavable microcrystalline texture; likely specific gravity near 2.6. The rounded shape and surface wear indicate natural water abrasion or tumbling.
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Physical properties
Hardness about 6.5–7 Mohs; tan, brown, gray, and reddish coloration; dull to waxy luster; massive, non-cleavable microcrystalline texture; likely specific gravity near 2.6. The rounded shape and surface wear indicate natural water abrasion or tumbling.
Formation & geological history
Likely formed by silica-rich replacement, cementation, or volcanic sediment alteration, followed by weathering and transport; precise age and locality cannot be determined from the image. Iron oxides produce the brown-red coloration.
Uses & applications
Suitable as a common lapidary rough, tumbled stone, cabochon, or decorative specimen; generally not suitable for structural construction. Commercial value is mainly aesthetic.
Geological facts
Jasper and chert are varieties of microcrystalline quartz and can look nearly identical in hand photographs. A steel file should generally fail to scratch it, while quartz should scratch glass.
Field identification & locations
Common in stream gravels, weathered volcanic terrains, and sedimentary deposits worldwide; inspect for conchoidal fracture, translucency at thin edges, and consistent quartz-like hardness. Identification remains provisional without tests or locality information.
