Quartzite Pebble

Physical Properties

Hardness: 7 on Mohs scale. Color: Tan, yellow, or off-white due to iron oxide staining. Luster: Vitreous to dull. Crystal structure: Trigonal (microcrystalline). Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Formation & Geological History

Formed through the metamorphism of quartz-rich sandstone under intense heat and pressure. This specific specimen has been rounded and smoothed by water erosion in a fluvial or coastal environment.

Uses & Applications

Used primarily as decorative gravel, in landscaping, as a construction aggregate, and occasionally in glass manufacturing if highly pure.

Geological Facts

Quartzite is so hard and chemically resistant that it often forms the tops of ridges and mountains because it resists weathering better than the rocks around it.

Field Identification & Locations

Identify in the field by its ability to scratch glass and its grainy, sugary texture under a lens. Found globally in riverbeds, beaches, and glacial deposits.

Identified on: 5/10/2026

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