Quartz Pebble

Silicon Dioxide (SiO2)

Rock Type: mineral

Quartz Pebble

Physical Properties

Hardness: 7 (Mohs scale); Color: White to creamy with yellowish iron staining; Luster: Vitreous/Waxy; Crystal Structure: Trigonal (though texture here is cryptocrystalline/massive); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & Geological History

Formed from the crystallization of silica-rich hydrothermal fluids or within igneous and metamorphic rocks. This specific specimen has been rounded and polished through fluvial processes (water erosion in a river or beach environment) over thousands of years.

Uses & Applications

Used in glassmaking, electronics, abrasive manufacturing, and as decorative landscaping stones or garden pebbles.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. This specimen exhibits 'iron staining,' which gives it the characteristic yellowish-brown streaks seen on its surface.

Field Identification & Locations

Identify in the field by its inability to be scratched by a steel knife (it will scratch glass) and its smooth, water-worn texture. Commonly found in riverbeds, beaches, and glacial deposits worldwide.

Identified on: 4/17/2026

Mode: Standard