mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to translucent
Luster: Vitreous to waxy

Identified February 12, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed during the final stages of magma cooling in igneous rocks or through hydrothermal activity in veins. The milky appearance is caused by tiny fluid inclusions (gas or liquid bubbles) trapped during crystal growth. Can be found in rocks ranging from millions to billions of years old.

Uses & applications

Used in the manufacturing of glass and ceramics, as an abrasive, in the semiconductor industry for silicon, and widely as tumbled stones for decorative use and metaphysical collecting.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. While clear quartz is more prized for optical uses, milky quartz contains microscopic 'ghost' bubbles that record the chemical environment of the Earth at the time of its formation.

Field identification & locations

Identified by its white color, inability to be scratched by a steel blade, and lack of cleavage planes. It is found globally, particularly in pegmatites, hydrothermal veins, and as river pebbles. Collectors look for pieces with interesting surface textures or associations with other minerals.