Quartz Pebble

Physical Properties

Hardness: 7 (Mohs scale); Color: Colorless, white, or light gray; Luster: Vitreous (glassy) to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & Geological History

Formed through the crystallization of molten magma or from hydrothermal veins. This specific specimen is a water-worn pebble, meaning it was likely eroded from a larger vein and smoothed over time by movement in a river or coastal environment.

Uses & Applications

Quartz is used in the manufacture of glass, electronics (oscillators), abrasives, and as a component in concrete. In pebble form, it is often used for landscaping, decoration, and as aquarium substrate.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'quarz', which has Slavic origins meaning 'hard'. It is piezoelectric, meaning it generates an electric charge in response to applied mechanical stress.

Field Identification & Locations

Identify in the field by its ability to scratch glass, its lack of cleavage (it breaks in irregular or curved shards), and its resistance to weathering. These pebbles are ubiquitous in riverbeds and on beaches worldwide.

Identified on: 4/16/2026

Mode: Standard