mineral

Quartz crystal specimen (possibly milky quartz with dark matrix)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Typically Mohs hardness 7, white to translucent with a vitreous luster and hexagonal crystal structure; quartz has no cleavage and conchoidal fracture. The dark area may be attached host rock or an inclusion, possibly mica or another sulfide mineral.

Identified August 23, 2026More mineral →

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Physical properties

Formation & geological history

Quartz crystallizes from silica-rich hydrothermal fluids, pegmatites, or cavities in igneous and metamorphic rocks; the specimen’s age cannot be determined from the image. Common sources include Brazil, Madagascar, the United States, and worldwide vein deposits.

Uses & applications

Used in glass, ceramics, abrasives, electronics, and scientific instruments; attractive crystals are collected and occasionally used in ornamental jewelry.

Geological facts

Quartz is one of Earth’s most abundant minerals and forms both macrocrystals and fine-grained varieties such as quartzite and chert.

Field identification & locations

Identify by its glassy luster, lack of cleavage, hardness sufficient to scratch ordinary glass, and commonly six-sided crystal faces. The image is low-resolution, so the dark inclusion and exact variety are uncertain.