mineral

Weathered quartz-rich rock, possibly chert or milky quartz

Mostly microcrystalline or crystalline quartz (SiO₂), identification uncertain from photograph

AI-generated identification · may be incorrect

Cream to pale tan, dull-to-waxy luster, rounded and water-worn, with irregular granular patches and possible iron-oxide staining. Quartz hardness is about Mohs 7, but the specimen’s surface appears weathered; cleavage is absent and fracture is typically conchoidal. Specific gravity is about 2.65.

Identified August 11, 2026More mineral →

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Physical properties

Formation & geological history

Likely a naturally weathered pebble formed from quartz-rich vein material or silica-rich sedimentary rock, later rounded by stream transport. Quartz is geologically widespread and may range from Precambrian to recent deposits; the specimen’s exact age cannot be determined visually.

Uses & applications

Common quartz-rich pebbles have little commercial value, though clear or attractive quartz is collected and used in glass, ceramics, electronics, abrasives, and jewelry.

Geological facts

The cream coloration may result from inclusions, clay, or iron oxides rather than the quartz itself. A scratch test with a steel file or glass can help: quartz should scratch glass and resist a steel nail.

Field identification & locations

The rounded form is plausible near 17.2°N, 89.1°W, where river gravels and weathered carbonate-terrane sediments occur. Confirm with a streak test, hardness test, and close inspection for conchoidal fracture; it could also be a pale limestone or silicified limestone, which would fizz with dilute hydrochloric acid.