mineral

Milky Quartz with Iron Oxide Staining

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on the Mohs scale; Color: White to translucent with brown/orange surface staining; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on the Mohs scale
Color: White to translucent with brown/orange surface staining
Luster: Vitreous to greasy

Identified March 16, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal solutions in veins or as a primary constituent of igneous and metamorphic rocks. This specimen likely comes from a hydrothermal vein where iron-rich groundwater later deposited limonite or hematite staining on the surface and within fractures.

Uses & applications

Used industrially as a source of silicon for electronics, as an abrasive, and in glassmaking. In collecting, it is often kept as a decorative specimen or used for metaphysical purposes.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The 'milky' appearance is caused by tiny fluid inclusions of gas and/or liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its ability to scratch glass (hardness) and lack of cleavage. It is found globally, particularly in mountainous regions and riverbeds as water-worn pebbles. Look for the characteristic white color and rocky, crystalline texture.

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