mineral

Tumbled gray stone, likely quartz-rich pebble

Probable microcrystalline quartz/chalcedony (SiO₂), possibly gray jasper or quartzite

AI-generated identification · may be incorrect

Rounded and polished, gray with pale internal patches and a waxy-to-dull luster; estimated Mohs hardness 6.5–7, no obvious cleavage, and moderate specific gravity around 2.6. The small size and smooth surface indicate tumbling.

Identified August 29, 2026More mineral →

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Physical properties

Formation & geological history

Likely formed from silica-rich volcanic or sedimentary material, later weathered into a pebble and human-polished; exact geological age and source cannot be determined from the image. Gray chalcedony and quartzite occur in many ancient and modern gravel deposits.

Uses & applications

Commonly used as a worry stone, craft material, or inexpensive lapidary specimen; not typically valuable as jewelry-grade material.

Geological facts

The pale triangular area may be a quartz vein, mineral inclusion, or surface reflection rather than a distinct crystal. Quartz-rich stones can scratch ordinary glass but should not be confused with man-made glass.

Field identification & locations

Test hardness against glass, inspect with a loupe for granular quartz or fibrous chalcedony, and check whether it leaves no streak on unglazed porcelain. Common sources include river gravels and lapidary suppliers.