Rock Identifier
Quartz Pebble (Silicon Dioxide (SiO2)) — mineral
mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Yellowish, tan, or off-white due to mineral staining; Luster: Vitreous to greasy; Crystal structure: Trigonal; Cleavage: None, exhibits conchoidal fracture; Specific gravity: 2.65

Hardness
7 on Mohs scale
Color
Yellowish, tan, or off-white due to mineral staining
Luster
Vitreous to greasy
Identified More mineral
Explore Quartz Pebble in the encyclopedia →

Identify your own rocks.

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

Physical properties

Hardness: 7 on Mohs scale; Color: Yellowish, tan, or off-white due to mineral staining; Luster: Vitreous to greasy; Crystal structure: Trigonal; Cleavage: None, exhibits conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Formed through weathering and water transport of quartz-rich rocks (such as granite or quartzite), where soft minerals break down and resistant quartz is smoothed by river or marine action over long geological timescales.

Uses & applications

Commonly used in landscaping, decorative gravel, tumbling, and as a natural specimen for rock collections.

Geological facts

Quartz is one of the most abundant minerals in the Earth's continental crust. Rounded pebbles like this often travel great distances in riverbeds before being deposited.

Field identification & locations

Can be identified in the field by its high hardness (scratches glass), lack of cleavage, and smooth, water-worn shape. Found globally in riverbeds, beaches, and glacial deposits.