Quartzite Pebble

Physical Properties

Hardness: 7 (Mohs scale), Color: tan-orange/peach, Luster: vitreous to waxy (when water-worn), Crystal: Hexagonal (microcrystalline), Cleavage: Indistinct, Specific Gravity: approx 2.65

Formation & Geological History

Formed through the regional metamorphism of quartz-rich sandstone. High heat and pressure Recrystallize the quartz grains. This specific specimen has been further shaped by fluvial (river) or glacial transport, resulting in a rounded pebble.

Uses & Applications

Raw material for glass making, building stone, decorative landscaping, and used in the manufacturing of silicon and abrasive products.

Geological Facts

Quartzite is so durable that it frequently outlasts the mountains it was formed in, becoming high-elevation mountain caps or rolling along river beds for thousands of miles without disintegrating.

Field Identification & Locations

Identify in the field by its hardness (will scratch glass easily) and its refusal to react with acid. Usually lacks the layered look of sedimentary sandstone. Found globally in river beds and beaches.

Identified on: 4/29/2026

Mode: Standard