mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: Opaque white to creamy tan
Luster: Vitreous to greasy

Identified March 17, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of magma or by hydrothermal activity in veins. Milky quartz gets its cloudy appearance from microscopic inclusions of fluids (gas or liquid) trapped during crystal growth over millions of years.

Uses & applications

Used in construction as a component of concrete, in the glass-making industry, as an abrasive, and occasionally for lapidary work or landscape decoration.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz found worldwide. Historically, it was sometimes used for stone tools when flint was unavailable.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage, and its characteristic 'greasy' luster on broken surfaces. It is found in nearly all geological environments but is especially common in quartz veins and riverbeds.