sedimentary

Tumbled quartz-rich pebble, likely jasper or chert

Microcrystalline quartz (SiO₂), possibly iron-stained jasper

AI-generated identification · may be incorrect

Mohs hardness about 6.5–7; opaque cream-yellow to tan, waxy to dull luster, very fine-grained and massive, with no visible cleavage. Rounded and smoothly polished, likely by natural water abrasion or tumbling.

Identified September 19, 2026More sedimentary →

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Physical properties

Formation & geological history

Most likely a silica-rich sedimentary pebble formed from microcrystalline quartz, with iron oxides producing the yellow coloration; exact age and locality cannot be determined from the image. Jasper and chert commonly form in silicified sedimentary or volcanic settings.

Uses & applications

Used as a low-cost decorative stone, tumbled specimen, craft material, and occasional cabochon; not typically valuable as jewelry-grade material.

Geological facts

The specimen resembles yellow jasper, but could also be chert, chalcedony, or a quartz-rich beach pebble. A steel knife should not easily scratch it, while quartz crystal may scratch its surface.

Field identification & locations

Commonly found in stream gravels, beaches, deserts, and areas with chert or jasper outcrops. A glassy fracture, strong translucency, or conchoidal break would favor chalcedony/chert over ordinary jasper.