mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: Opaque white to translucent, Luster: Vitreous to greasy, Crystal System: Trigonal (often hexagonal prisms), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified July 15, 2026More mineral →

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Physical properties

Formation & geological history

Forms through hydrothermal activity as mineral-rich aqueous solutions cool in rock fractures or during late-stage igneous crystallization; may also form in metamorphic environments. Its white color comes from microscopic inclusions of fluids and gases trapped during formation.

Uses & applications

Used in glass making, electronics (piezoelectric properties), abrasives, ornamental stone, and landscaping. High-purity quartz is essential for making solar panels and silicon chips.

Geological facts

Milky Quartz is one of the most common varieties of crystalline quartz found on Earth. It is the color of milk due to countless tiny bubbles of gas or liquid trapped within the crystal when it grew.

Field identification & locations

Identified in the field by its distinct white color, inability to be scratched by steel, and lack of cleavage (it breaks in irregular shards like glass). It is ubiquitous worldwide and frequently found as pebbles in riverbeds or as veins in bedrock.