Quartz (Milky Quartz)

Physical Properties

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous (glassy) to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & Geological History

Formed through the cooling of silica-rich magma or from hydrothermal veins. This specimen appears water-worn, likely from a fluvial (river) environment where it has been tumbled over time.

Uses & Applications

Used in glassmaking, abrasives, electronics (due to piezoelectric properties), and as a gemstone or decorative stone.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. The 'milky' appearance is caused by tiny fluid or gas inclusions trapped during the crystal's growth.

Field Identification & Locations

Identify by its hardness (it will scratch glass) and lack of cleavage. Look for it in riverbeds, mountains, and gravel pits. It is often found as veins in other host rocks.

Identified on: 4/27/2026

Mode: Standard