Quartz Pebble (Milky Quartz)

Silicon Dioxide (SiO2)

Rock Type: mineral

Quartz Pebble (Milky Quartz)

Physical Properties

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

Formation & Geological History

Formed from silica-rich hydrothermal fluids cooling in veins or as a major constituent of igneous rocks like granite. This specific specimen has been polished smooth by water erosion (river or beach action) or a rock tumbler.

Uses & Applications

Used in glassmaking, ceramics, as an abrasive, in decorative landscaping, and occasionally as a low-cost gemstone or healing crystal in the metaphysical market.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its cloudy appearance from tiny fluid inclusions of gas or liquid trapped during crystal growth.

Field Identification & Locations

Identify in the field by its inability to be scratched by a steel knife (H=5.5) and its lack of cleavage planes. Found globally in almost all geological environments, especially riverbeds and beaches.

Identified on: 4/19/2026

Mode: Standard