mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Milky white to translucent with iron staining; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal (though rounded by erosion); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Milky white to translucent with iron staining
Luster: Vitreous to waxy

Identified March 2, 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 through the cooling of silica-rich hydrothermal fluids or magma within veins. The rounded shape indicates it has been subjected to significant fluvial or coastal erosion, likely over thousands of years.

Uses & applications

Industrial uses include glass making and abrasives. As a pebble, it is used in landscaping, decorative river rock, and as an entry-level specimen for hobbyist rock tumbling.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. This specific specimen shows milky inclusions which are caused by tiny pockets of gas or liquid trapped during the crystal's formation.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife and its lack of cleavage planes. Found globally in riverbeds, beaches, and glacial till. Collectors look for clarity or unique inclusions.