mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to pale cream; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

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

Identified February 21, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to pale cream; 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 primary constituent in igneous rocks like granite. The milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and electronics (due to piezoelectric properties). In crushed form, it serves as an abrasive or construction aggregate. Polished specimens are used in jewelry and lapidary art.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While often overlooked for clearer varieties like rock crystal, it can contain traces of gold in hydrothermal vein deposits, making it a primary indicator for prospectors.

Field identification & locations

Identify in the field by its ability to scratch glass, lack of cleavage planes, and waxy luster. It is ubiquitous worldwide, especially in mountain ranges and riverbeds as water-worn pebbles. Collectors look for unique vein patterns or associated minerals.