sedimentary

Chert or chalcedony pebble

Microcrystalline quartz (SiO₂), likely chert with chalcedonic texture

AI-generated identification · may be incorrect

Small rounded, brown-orange, opaque to slightly translucent pebble with waxy luster and irregular pale internal patches. Quartz hardness is about Mohs 7; no visible cleavage, conchoidal fracture, and specific gravity near 2.6.

Identified August 25, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from silica-rich groundwater or replacement of sediment, commonly in limestone and other sedimentary rocks; later rounded by stream or surface transport. Its exact geological age cannot be determined from the photograph.

Uses & applications

Mostly a collector or decorative specimen; suitable for tumbling, cabochons, beads, and flint-like tools. It has little commercial value at this size.

Geological facts

The pale areas may be chalcedony, weathering, or small cavities rather than separate crystals. Brown coloration commonly comes from iron oxides.

Field identification & locations

Test carefully on an inconspicuous edge: it should scratch ordinary glass but not be scratched by a steel knife. The regional setting near 35.4°N, 45.6°E is compatible with chert-bearing sedimentary formations and transported pebbles, though a precise locality is needed for certainty.