Rock Identifier
Likely polished quartz or quartz-rich pebble (Quartz (silicon dioxide, SiO₂), possibly milky quartz) — mineral
mineral

Likely polished quartz or quartz-rich pebble

Quartz (silicon dioxide, SiO₂), possibly milky quartz

AI-generated identification · may be incorrect

Small rounded specimen with a bright vitreous-to-waxy white reflection and pale translucent body. Quartz has Mohs hardness 7, no cleavage, conchoidal fracture, hexagonal crystal structure, and specific gravity about 2.65; the intense glare prevents confident assessment of color and texture.

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Physical properties

Small rounded specimen with a bright vitreous-to-waxy white reflection and pale translucent body. Quartz has Mohs hardness 7, no cleavage, conchoidal fracture, hexagonal crystal structure, and specific gravity about 2.65; the intense glare prevents confident assessment of color and texture.

Formation & geological history

Quartz commonly crystallizes from silica-rich hydrothermal fluids, igneous melts, or sedimentary veins and can survive erosion as rounded pebbles. Its geological age is indeterminate from the photograph and may range from recent sediment to ancient bedrock.

Uses & applications

Used in glass, ceramics, electronics, abrasives, engineered stone, and as a low-cost gemstone or cabochon. Clear, well-formed crystals may have modest collecting value.

Geological facts

The white flash is consistent with a polished or naturally smooth quartz surface, but could also arise from another pale hard mineral. A scratch test and close examination under diffuse light are needed for reliable identification.

Field identification & locations

Common in quartz veins, granite-derived gravels, riverbeds, and metamorphic rocks worldwide. Test whether it scratches steel or glass, shows conchoidal fracture, and lacks cleavage; avoid destructive tests if it is valuable.