Rock Identifier
Likely smoky quartz-bearing rock or quartz crystal (Quartz, silicon dioxide (SiO₂), possibly smoky quartz with iron- or irradiation-related coloration) — mineral
mineral

Likely smoky quartz-bearing rock or quartz crystal

Quartz, silicon dioxide (SiO₂), possibly smoky quartz with iron- or irradiation-related coloration

AI-generated identification · may be incorrect

Translucent brown-gray to honey color, vitreous luster, irregular to weak conchoidal fracture, and apparent crystalline faces; Mohs hardness 7, no cleavage, specific gravity about 2.65. The rough, granular appearance suggests quartz in a matrix rather than a clean single crystal.

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Physical properties

Translucent brown-gray to honey color, vitreous luster, irregular to weak conchoidal fracture, and apparent crystalline faces; Mohs hardness 7, no cleavage, specific gravity about 2.65. The rough, granular appearance suggests quartz in a matrix rather than a clean single crystal.

Formation & geological history

Quartz crystallizes from silica-rich hydrothermal fluids or late-stage igneous cavities; smoky coloration commonly develops from irradiation acting on trace aluminum. The specimen’s exact geological age and locality cannot be determined from the image.

Uses & applications

Quartz is used in glass, ceramics, abrasives, electronics, and optical components; attractive smoky quartz is cut for jewelry or kept as a mineral specimen.

Geological facts

Quartz is one of Earth’s most abundant minerals and has a trigonal crystal structure. Brown coloration can also result from iron staining or surface weathering, so confirmed identification may require hardness and streak tests.

Field identification & locations

Common localities include Brazil, Madagascar, the Alps, Colorado, and Arkansas. Test by scratching glass (quartz should scratch it) while avoiding damage; a close inspection may reveal hexagonal crystal faces.