mineral

Milky quartz

Quartz (silicon dioxide, SiO₂)

AI-generated identification · may be incorrect

Typically white to translucent with a glassy-to-waxy luster; hardness 7 Mohs, no cleavage, conchoidal fracture, trigonal crystal structure, and specific gravity about 2.65. The specimen appears rough, massive, and partly translucent, possibly with minor iron staining or associated feldspar.

Identified August 11, 2026More mineral →

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Physical properties

Formation & geological history

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

Uses & applications

Used extensively in glass, ceramics, foundry sand, electronics, abrasives, and engineered stone; attractive pieces are sold as inexpensive mineral specimens. It is generally not gem quality.

Geological facts

Quartz is one of Earth’s most abundant minerals and is piezoelectric, producing an electrical charge under pressure. Milky appearance results mainly from microscopic fluid inclusions and structural defects.

Field identification & locations

Identify it by its hardness—scratches glass or steel—and lack of cleavage; a streak test is white, and a knife usually will not scratch it. Common worldwide, especially in quartz veins, granites, pegmatites, and metamorphic belts.