mineral

Milky Quartz

Quartz / Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to creamy white; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white to creamy white
Luster: Vitreous (glassy) to greasy

Identified March 9, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of magma or by hydrothermal activity when hot water solutions containing silica cool in veins. Milky quartz gets its characteristic white color from microscopic inclusions of fluid (gas or liquid) that were trapped during crystal growth. Found in various geological ages from Precambrian to recent.

Uses & applications

Used widely in the manufacturing of glass, ceramics, and abrasives. Because of its hardness, it is used in sandpaper and sandblasting. In jewelry, it is often cut into cabochons or beads. It is also an important ore of silicon for computer chips.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by many ancient cultures to create tools and arrowheads. It is often a 'mother rock' for gold, meaning gold is frequently found embedded within quartz veins.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), its opaque white color, and its lack of cleavage (it breaks in irregular, shell-like curves). It is found globally, common in mountain ranges, riverbeds, and as veins in metamorphic and igneous rocks.