mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to pale tan; Luster: Vitreous to greasy; Crystal structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Cloudy white to pale tan
Luster: Vitreous to greasy

Identified July 5, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to pale tan; Luster: Vitreous to greasy; Crystal structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Quartz forms in a variety of environments, primarily through the cooling of silica-rich magma or from hydrothermal veins. This specimen appears to be a water-worn or weathered piece of vein quartz.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), and as a common gemstone/decorative stone in landscaping and jewelry.

Geological facts

Quartz is the second most abundant mineral in the Earth's continental crust. Pure quartz is clear, but 'milky quartz' gets its white appearance from tiny fluid inclusions trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (it will scratch glass) and its lack of cleavage. It is extremely common in riverbeds and as veins in metamorphic and igneous rocks worldwide.