mineral

Milky quartz crystal

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Mohs hardness 7; translucent white to pale gray, with a vitreous luster and irregular conchoidal fracture. It has a hexagonal crystal structure but this specimen appears as a rough, broken crystal fragment; cleavage is absent and specific gravity is about 2.65.

Identified August 20, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich fluids crystallize in veins, cavities, and pegmatites, commonly in igneous and metamorphic rocks. Quartz is widespread from Precambrian rocks to modern hydrothermal deposits; the exact age cannot be determined from the image.

Uses & applications

Used extensively in glass, ceramics, electronics, abrasives, and engineered stone; attractive pieces are collected or used decoratively, though milky quartz is usually not gem-quality.

Geological facts

The cloudy appearance results from microscopic fluid inclusions, fractures, or mineral impurities. Quartz is one of Earth’s most abundant and chemically resistant minerals.

Field identification & locations

Identify it by its glassy luster, hardness, lack of cleavage, and inability to be scratched by a steel knife; it should scratch ordinary glass. Common localities include Brazil, Madagascar, the United States, and alpine or hydrothermal veins worldwide.