mineral

Smoky Quartz (with Hematite inclusions)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Brownish-gray, translucent to opaque; Luster: Vitreous to sub-waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Brownish-gray, translucent to opaque
Luster: Vitreous to sub-waxy

Identified March 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed in igneous or metamorphic environments, primarily in pegmatite veins or hydrothermal veins. This specimen likely formed through slow hydrothermal precipitation of silica-rich fluids under high pressure, with trace amounts of aluminum and natural irradiation providing the smoky color.

Uses & applications

Used in jewelry as a semi-precious gemstone, in decorative carvings, and as a popular mineral specimen for collectors. In industry, high-purity quartz is used in electronics and glassmaking.

Geological facts

The 'smoky' color is caused by natural irradiation from surrounding rocks that creates color centers around aluminum impurities within the crystal lattice. It is the national gem of Scotland, where it is known as 'Cairngorm'.

Field identification & locations

Identify in the field by its hardness (will scratch glass easily), lack of cleavage, and the distinct brownish hue. Often found in mountainous regions or inside vugs (cavities) in granitic pegmatites. Collectors should look for sharp crystal faces and clarity.

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