mineral

Milky Quartz (Tumbled)

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous (glassy) to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous (glassy) to waxy

Identified March 24, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous (glassy) to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal veins or within igneous pegmatites. The milky white appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth. They are found in geological environments ranging from Precambrian to Cenozoic eras.

Uses & applications

Used widely in lapidary for tumbled stones, beads, and carvings. Industrially, quartz is used in glass making, abrasives, and as a source of silicon for electronics, though higher purity specimens are typically preferred for technical applications.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by many indigenous cultures for tool making due to its conchoidal fracture which creates sharp edges. It is often found in massive form rather than distinct terminated crystals.

Field identification & locations

Identify in the field by its hardness (it will easily scratch glass), lack of cleavage, and white 'milky' opacity. It is found globally in riverbeds, mountains, and mines. Collectors should look for smoothness and the absence of large cracks in tumbled versions.

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