mineral

Milky Quartz with Mineral Inclusions

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to translucent with black/brown mineral inclusions (likely iron or manganese oxides); Luster: Vitreous to greasy; Crystal Structure: Hexagonal (Trigonal); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Luster: Vitreous to greasy

Identified March 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich hydrothermal fluids in veins or pegmatites. The 'milky' appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth. Can be found in geological formations ranging from Precambrian to Cenozoic.

Uses & applications

Used industrially as a source of silicon for semiconductors, glass making, and abrasives. In collecting, it is often used for lapidary work, cabochons, or as decorative garden stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of crystalline quartz. The dark staining or inclusions seen in this specimen are often referred to as 'dendritic' if they are tree-like, or simply mineral staining from nearby ore deposits.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (test for hardness 7) and its lack of cleavage. Often found as rounded river stones or as blocky white veins in host rock. It is ubiquitous worldwide, especially in mountainous or volcanic regions.

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