sedimentary

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Tan to creamy white; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Tan to creamy white
Luster: Vitreous to waxy

Identified June 24, 2026More sedimentary →

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Physical properties

Hardness: 7 on Mohs scale; Color: Tan to creamy white; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through the weathering and erosion of igneous or metamorphic rocks containing quartz. This specimen has been rounded and smoothed by water transport in a fluvial or beach environment.

Uses & applications

Commonly used in landscaping, road construction (aggregate), and occasionally for decorative stone collecting. Purer quartz is used in glass and electronics.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. These rounded pebbles are often found in 'river rock' mixes and can withstand millions of years of erosion.

Field identification & locations

Identified by its hardness (will scratch glass), lack of breakage lines (cleavage), and smooth, rounded water-worn texture. Found globally in riverbeds, glacial deposits, and beaches.