Rock Identifier
Milky Quartz (Silicon Dioxide (SiO2)) — mineral
mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness
7 (Mohs scale)
Color
White to translucent
Luster
Vitreous to greasy
Identified More mineral

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Physical properties

Hardness: 7 (Mohs scale); Color: 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 crystallization of silica-rich hydrothermal fluids in veins or as a late-stage mineral in igneous rocks like granite. The 'milky' appearance is caused by tiny fluid or gas inclusions trapped during crystal growth.

Uses & applications

Used in industry for glassmaking, abrasives, and as a source of silicon for semiconductors. In construction, it is used as crushed stone or decorative gravel. Occasionally used for carvings and tumbled stones in jewelry.

Geological facts

Quartz is one of the most abundant minerals on Earth's crust. 'Milky Quartz' is specifically known for being the 'mother of gold' because it is often the host rock for hydrothermal gold deposits.

Field identification & locations

Identify in the field by its ability to scratch glass, lack of cleavage (it breaks into irregular, sharp shards), and its snowy white color. Very common in mountainous terrain, riverbeds, and as garden landscaping stone.