mineral

Quartz vein in weathered host rock

Milky quartz (SiO₂), likely in a granitic or metamorphic matrix

AI-generated identification · may be incorrect

White, translucent-to-opaque quartz with a glassy to waxy luster and irregular fracture; Mohs hardness 7, no cleavage, trigonal crystal structure, and specific gravity about 2.65. The surrounding brown-gray matrix appears weathered and may contain feldspar, mica, and iron oxides.

Identified August 8, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich hydrothermal fluids fill fractures and crystallize, commonly during cooling of igneous bodies or metamorphism. The exact geological age cannot be determined from the image and depends on the host rock.

Uses & applications

Quartz is used in glass, ceramics, engineered stone, electronics, and abrasives; attractive specimens are collected but are usually of modest gem value.

Geological facts

Milky color results from microscopic fluid inclusions, fractures, or impurities that scatter light. Iron-oxide staining accounts for the rusty brown coloration around the vein.

Field identification & locations

Identify it by its hardness, lack of cleavage, white translucent appearance, and inability to scratch it with a steel knife; it should scratch glass. Common in granites, schists, gneisses, and hydrothermal veins worldwide.