mineral

Milky quartz (likely iron-stained quartz)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

White to translucent, glassy-to-dull luster, irregular fracture, and no obvious cleavage; Mohs hardness 7, trigonal crystal structure, specific gravity about 2.65. Brown flecks or staining may be iron oxides or attached host material.

Identified September 22, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich fluids crystallize in veins, cavities, or pegmatites; the specimen’s exact geological age and locality cannot be determined from the image. Commonly associated with feldspar, mica, and metallic oxides.

Uses & applications

Used extensively in glass, ceramics, abrasives, electronics, and engineered stone; attractive pieces are sold as inexpensive collector specimens or lapidary material. Typical value is about $1–$15 for a small ordinary fragment, more if crystallized or locality-specific.

Geological facts

Quartz is one of Earth’s most abundant minerals and is resistant to weathering, allowing it to accumulate in sand and sediment. Milky appearance results from microscopic fluid inclusions, fractures, or impurities.

Field identification & locations

Identify by its white translucent appearance, hardness sufficient to scratch ordinary glass, and lack of cleavage; avoid testing valuable specimens destructively. Common worldwide, especially in hydrothermal veins and granite-related pegmatites.