sedimentary or metamorphic

Rounded quartz-rich pebble, likely sandstone or quartzite

Quartz sandstone (quartz arenite) or low-grade quartzite; predominantly SiO₂

AI-generated identification · may be incorrect

Light gray-beige, fine-grained, dull to subtly sugary luster, and well-rounded from abrasion. Quartz has Mohs hardness 7; the specimen appears compact and lacks visible cleavage, though the image cannot confirm texture or density.

Identified September 7, 2026More sedimentary or metamorphic →

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Physical properties

Formation & geological history

Likely formed from cemented quartz sand, possibly later metamorphosed into quartzite, then weathered and rounded in a stream or glacial deposit. Its precise geological age and formation cannot be determined from the photograph.

Uses & applications

Common sandstone is used for building stone, paving, aggregate, and landscaping; quartzite is used for durable construction stone, countertops, and aggregate. This small pebble has negligible commercial value.

Geological facts

The pale color and granular surface suggest abundant quartz, but feldspar-rich granite, gneiss, or light-colored volcanic rock are alternatives. A fresh broken surface and acid, streak, and hardness tests would improve identification.

Field identification & locations

Look for individual sand grains and cement in sandstone; quartzite is typically harder, more fused, and fractures through grains. Common in river gravels, beaches, glacial tills, and weathered uplands.