mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Milky white to translucent
Luster: Vitreous (glassy) to greasy

Identified April 19, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous (glassy) 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 veins or within cooling igneous magma bodies. This specific specimen appears water-worn, indicating it was eroded and transported by a river or stream over geological time.

Uses & applications

Used in glassmaking, abrasives, electronics (due to piezoelectric properties), construction as an aggregate, and for ornamental carving or landscaping.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its cloudy appearance from microscopic inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (it should scratch glass and steel knives), lack of cleavage, and conchoidal (shell-like) fracture patterns. Frequently found in riverbeds, mountains, and gravel deposits globally.