mineral

Milky Quartz (Micro-specimen)

Silicon Dioxide (SiO2)

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

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

Identified March 21, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Opaque 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. The white color is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth. Can be found in geological formations ranging from Precambrian to Quaternary periods.

Uses & applications

Used in the production of glass, ceramics, and abrasives. In electronics, it is used for its piezoelectric properties. Low-grade specimens are used as decorative aggregate or in construction. Quality crystals are faceted for jewelry or collected by mineral enthusiasts.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz. Throughout history, various cultures have used quartz to make 'stone' tools and ritual objects.

Field identification & locations

Identify in the field by its hardness (will scratch glass and steel), white opaque appearance, and lack of cleavage. Commonly found in granite pegmatites, hydrothermal veins, and as pebbles in riverbeds or beaches worldwide.

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