Quartzite Pebbles

Physical Properties

Hardness: 7 on Mohs scale; Color: Cream, white, or light tan; Luster: Vitreous to waxy; Texture: Fine-grained, smooth due to water erosion; Cleavage: None; Specific Gravity: 2.6-2.7.

Formation & Geological History

Formed from the metamorphism of quartz sandstone under intense heat and pressure. The pebble shape indicates it was later eroded and smoothed by high-energy water environments like rivers or coastal beaches.

Uses & Applications

Used as decorative landscaping stones, aquarium substrate, and historically as a component in glass making or construction aggregate.

Geological Facts

Quartzite is one of the hardest and most chemically resistant rocks on the Earth's surface. It survives extreme weathering that would break down other rock types into sand.

Field Identification & Locations

Identify by its extreme hardness (cannot be scratched by a steel knife) and its lack of reaction to acid. It is commonly found in riverbeds, glacial tills, and along coastlines.

Identified on: 5/13/2026

Mode: Standard