sedimentary

Rounded quartz-rich pebbles

Likely quartzite or quartz-rich sandstone; predominantly microcrystalline quartz (SiO₂)

AI-generated identification · may be incorrect

White to pale gray, matte to subtly sugary luster, fine-grained and water-worn; quartz hardness is about Mohs 7, with no visible cleavage and typical specific gravity near 2.65. The smooth shape indicates natural abrasion or tumbling.

Identified September 5, 2026More sedimentary →

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Physical properties

Formation & geological history

Probably derived from weathered quartzite or quartz-rich sandstone and rounded in a river, beach, or commercial tumbler; the original rock may be Precambrian to younger, but the image cannot establish age.

Uses & applications

Used as decorative pebbles, landscaping stone, aquarium media, crafts, and jewelry or worry stones; not generally valuable as gem material.

Geological facts

The uniform pale color and rounded form are consistent with common quartz-rich beach or river pebbles, though similar-looking limestone or marble is possible without testing.

Field identification & locations

Check hardness: quartz-rich pieces scratch ordinary glass and do not fizz in dilute hydrochloric acid; calcite-rich marble or limestone fizzes and is softer. Common worldwide, especially in quartz-bearing river gravels and beaches.