mineral

Smoky Quartz with Calcite/Quartz Veining

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Translucent dark grey to brownish (smoky); Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Translucent dark grey to brownish (smoky)
Luster: Vitreous (glassy)

Identified April 6, 2026More mineral →

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Physical properties

Formation & geological history

Formed in igneous or metamorphic environments like pegmatites or hydrothermal veins. The smoky color is caused by natural irradiation of trace aluminum impurities over millions of years.

Uses & applications

Commonly used in jewelry, as decorative display specimens, and in spiritual/metaphysical practices. Occasionally used in electrical components for its piezoelectric properties.

Geological facts

Smoky quartz is the national gem of Scotland, where it is known as 'Cairngorm.' It can range from nearly transparent to almost completely black (a variety known as Morion).

Field identification & locations

Identify in the field by its hardness (will scratch glass), glassy luster, and typical smoky transparency. It is often found in mountainous regions globally.

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