mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Semi-translucent yellow-brown; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Semi-translucent yellow-brown
Luster: Vitreous to waxy

Identified May 5, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 7 on Mohs scale; Color: Semi-translucent yellow-brown; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Formed through hydrothermal processes or silica-rich crystallization from magma. This specific specimen has been water-worn and smoothed in a river, beach, or glacial environment over thousands of years.

Uses & applications

Commonly used as decorative gravel, in glass manufacturing once crushed, or as pocket stones/tumbled rocks for collectors. Primarily a source of silicon for electronics and semiconductors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the Greek word 'krustallos', meaning ice, as ancient Greeks believed quartz was permanently frozen water.

Field identification & locations

Identified by its high hardness (cannot be scratched by steel), glassy appearance, and lack of cleavage. Look for it in riverbeds, lake shores, and gravel pits across the globe.