mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to foggy translucent, often stained with iron oxides (reddish-brown); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Luster: Vitreous to greasy

Identified March 1, 2026More mineral →

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Physical properties

Formation & geological history

Forms in hydrothermal veins or as a primary constituent in igneous, metamorphic, and sedimentary rocks. Milky appearance is caused by tiny inclusions of gas and liquid trapped during crystallization. Most specimens vary from millions to billions of years old.

Uses & applications

Used in construction as road metal and concrete aggregate. In industry, it is a source of silica for glassmaking, abrasives, and refractory materials. Lower quality specimens like this are used for landscaping or decorative stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, it was used by ancient civilizations for tools like scrapers and projectile points due to its hardness and sharp edges when broken.

Field identification & locations

Identified in the field by its hardness (it will easily scratch glass or steel), lack of cleavage, and white 'milky' look compared to clear quartz. Frequently found in riverbeds, mountains, and garden landscapes worldwide.