Quartzite Pebble

Physical Properties

Hardness: 7 on Mohs scale; Color: whitish, gray, beige; Luster: vitreous to dull; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.6-2.7

Formation & Geological History

Formed through the metamorphism of quartz-rich sandstone under intense heat and pressure. Most specimens are Proterozoic to Paleozoic in age. This specific shape is the result of fluvial or coastal erosion.

Uses & Applications

Used in construction as road ballast, in glass manufacturing as a silica source, and as decorative stone in landscaping. Smooth pebbles are often used in massage therapy or as pocket stones.

Geological Facts

Quartzite is so durable that it often survives intense mechanical weathering, remaining as rounded pebbles long after the surrounding softer rocks have turned to soil.

Field Identification & Locations

Identify in the field by its extreme hardness (it will scratch glass) and lack of reactivity to acid. Found globally in riverbeds, beaches, and glacial till. Highly common find for collectors.

Identified on: 5/15/2026

Mode: Standard