mineral

Milky quartz (possibly chalcedony)

Quartz, SiO₂; likely massive or cryptocrystalline quartz

AI-generated identification · may be incorrect

White to pale bluish translucent, vitreous-to-waxy luster, irregular conchoidal fracture, and no obvious cleavage; Mohs hardness 7, specific gravity about 2.65. The cloudy appearance comes from microscopic fluid inclusions or fine internal fractures.

Identified September 11, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich fluids precipitate in cavities, veins, or fractures, commonly in igneous and metamorphic rocks; individual specimens may range from ancient Precambrian to much younger. The orange spot may be iron-oxide staining or an inclusion.

Uses & applications

Used for decorative stone, carvings, abrasives, countertops, and glass manufacture; attractive translucent pieces are collected but are generally inexpensive.

Geological facts

Quartz is one of Earth’s most abundant minerals and crystallizes in the trigonal system, though massive specimens may show no visible crystal faces.

Field identification & locations

Identify by its glassy/waxy appearance, lack of cleavage, conchoidal fracture, and ability to scratch ordinary glass; a steel blade should not scratch it. Common worldwide, especially in hydrothermal veins, pegmatites, and quartz-rich metamorphic rocks.