mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 (Mohs scale); Color: White to translucent with yellowish/reddish staining (iron oxides); Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 (Mohs scale)
Luster: Vitreous to greasy

Identified April 10, 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 crystallization of silica-rich hydrothermal fluids in veins or as a constituent of igneous and metamorphic rocks. The 'milky' appearance is caused by tiny fluid inclusions trapped during growth. Found in almost all geological environments.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), various industrial fillers, and as an ornamental gemstone or garden stone.

Geological facts

Quartz is the most abundant and widely distributed mineral found at Earth's surface. Milky quartz is the most common variety of quartz. The reddish and yellow tints in this specific specimen are likely 'limonite' or 'hematite' staining from weathering.

Field identification & locations

Identify by its ability to scratch glass, lack of cleavage, and waxy/vitreous luster. Common in mountain ranges, riverbeds, and as veins in larger rock outcrops. It is a 'foundational' mineral for amateur collectors.