sedimentary

Rounded sandstone or quartz-rich sedimentary pebble

Likely quartz arenite/subarkose; exact identification requires testing

AI-generated identification · may be incorrect

Pale tan-orange, fine-grained, rounded and water-worn, with a dull earthy luster and possible iron-oxide staining. Likely hardness around 6–7 if quartz-rich; weak or absent cleavage, porous to variable density, and no visible crystals.

Identified September 10, 2026More sedimentary →

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Physical properties

Formation & geological history

Probably a naturally eroded sedimentary pebble formed from cemented sand, commonly by silica, calcite, or iron oxides. Its depositional age cannot be determined from the photograph; later abrasion rounded it in a stream, beach, or gravel deposit.

Uses & applications

Common sandstone is used for building stone, paving, landscaping, and aggregate; this small specimen has mainly educational or decorative value.

Geological facts

The orange coloration commonly comes from hematite or limonite coatings. A white streak or patch may represent quartz-rich cement, weathered feldspar, or a superficial mineral deposit.

Field identification & locations

Look for visible sand grains, sedimentary layering, and reaction to dilute hydrochloric acid if calcite-cemented; quartz-rich pieces do not fizz and can scratch glass. Common worldwide in sedimentary basins, river gravels, and beaches.