mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to semi-translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White to semi-translucent
Luster: Vitreous to greasy

Identified May 17, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to semi-translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms through the crystallization of silica-rich hydrothermal fluids in veins or pegmatites; often found in igneous or metamorphic host rocks. Its white color is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), and as decorative stones or gravel in landscaping.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by ancient civilizations for stone tools and carvings. It is often found in gold-bearing veins.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and translucent white appearance. It is found globally in many geological environments including mountain ranges and riverbeds.