mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to tan/yellowish (due to iron stains or impurities); Luster: Vitreous to greasy; Crystal Structure: Trigonal (often crypto-crystalline in worn river pebbles); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Luster: Vitreous to greasy

Identified May 21, 2026More mineral →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Formed from hydrothermal veins or the cooling of silica-rich magma; these specific specimens are river-worn or alluvial pebbles shaped by water erosion over hundreds to thousands of years. Found in most geological environments globally.

Uses & applications

Industrial use in glassmaking, abrasives, and electronics. Small pebbles are often used in landscaping, gravel for construction, or as pocket stones for beginners.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. These rounded shapes indicate the stones have traveled long distances in a high-energy water environment, such as a riverbed or beach.

Field identification & locations

Identify in the field by its ability to scratch glass and lack of cleavage. Look for the translucent look and smooth, rounded water-worn surfaces in creek beds or shorelines.