Quartzite Pebble

Physical Properties

Hardness: 7 (Mohs scale); Color: Grayish-white to tan; Luster: Vitreous to waxy; Structure: Granulose texture with interlocking quartz grains; Non-foliated; High specific gravity around 2.65.

Formation & Geological History

Formed from the metamorphism of quartz-rich sandstone under intense heat and pressure. This specific specimen has been further shaped and smoothed by river or beach water erosion (water-worn).

Uses & Applications

Used as aggregate in construction, as a decorative stone in landscaping, or as high-quality building stone. Polished versions are used in jewelry and rock collections.

Geological Facts

Quartzite is so durable that it often outlasts the mountain ranges in which it was formed, frequently surviving as pebbles in riverbeds long after surrounding softer rocks have eroded away.

Field Identification & Locations

Identify in the field by its hardness (it can scratch glass easily) and its sugary/granular appearance when broken. Very common in regions with ancient mountain belts or glacial deposits.

Identified on: 4/14/2026

Mode: Standard