mineral

Milky quartz vein in altered host rock

Quartz (SiO₂), likely with feldspar, mica, and iron-oxide alteration

AI-generated identification · may be incorrect

White to translucent quartz has a vitreous-to-waxy luster, uneven fracture, and Mohs hardness 7; the greenish-gray host appears finer-grained and altered, with brown iron-oxide staining. Quartz is trigonal and lacks cleavage, while feldspar or mica in the host may show cleavage.

Identified September 4, 2026More mineral →

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Physical properties

Formation & geological history

Likely formed when silica-rich hydrothermal fluids filled fractures in older igneous or metamorphic rock; the exact age and locality cannot be determined from the image. Iron oxidation produced the brown staining and weathered surface.

Uses & applications

Quartz specimens are collected, and quartz is used in glass, abrasives, electronics, and engineered stone; the host rock has little construction value unless present in large, sound masses.

Geological facts

Milky quartz becomes opaque because microscopic fluid inclusions and defects scatter light. The specimen is more accurately called a quartz vein or quartz-rich breccia than a single pure mineral sample.

Field identification & locations

Identify it by its white glassy quartz, hardness, lack of cleavage, and inability to scratch with a steel knife while potentially scratching glass; the green-gray matrix may indicate chlorite- or epidote-rich alteration. Common in hydrothermal veins worldwide.