mineral

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 (Mohs scale)
Color: White to translucent
Luster: Vitreous to greasy

Identified April 3, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous 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. Milky quartz specifically gets its appearance from tiny fluid or gas bubbles trapped during crystal growth. Found in various geological ages ranging from Precambrian to recent.

Uses & applications

Used in glassmaking, as an abrasive, in decorative landscaping, and occasionally as a low-cost gemstone or for metaphysical collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The white 'milky' color is caused by microscopic inclusions of liquids or gases that were trapped as the crystal formed over millions of years.

Field identification & locations

Identify by its ability to scratch glass (hardness 7), its lack of cleavage, and its waxy/vitreous luster. Common in riverbeds and mountainous terrain worldwide.