metamorphic

Rounded quartz-rich pebble, likely quartzite or quartz sandstone

Quartzite (mostly SiO₂), possibly ferruginous quartz sandstone

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; pale pink, tan, and gray with rusty orange iron-oxide staining; matte to slightly sugary/vitreous luster. Dense, fine-grained, and massive, with no obvious cleavage; quartzite typically has specific gravity near 2.6–2.7.

Identified September 6, 2026More metamorphic →

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Physical properties

Formation & geological history

Likely formed from quartz-rich sandstone that was compacted and metamorphosed, though a weakly cemented quartz sandstone is also possible. Its rounded shape indicates prolonged transport by water or abrasion; precise age and source cannot be determined from the image.

Uses & applications

Commonly used as aggregate, riprap, landscaping stone, and sometimes dimension stone. Attractive pieces may be collected or used in crafts, but this specimen has no apparent gem-grade value.

Geological facts

The pink and orange colors probably result from iron oxides coating or staining quartz grains. Quartzite can be difficult to distinguish from quartz sandstone without examining grain boundaries and testing hardness.

Field identification & locations

Look for granular quartz texture, resistance to scratching by a steel knife, and inability to scratch glass only if sufficiently quartz-rich; quartzite usually scratches glass. Common in river gravels and areas underlain by metamorphic or quartz-rich sedimentary rocks.