mineral

Smoky Quartz (with Iron Inclusions)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale); Color: Grayish-brown to smoky black with orange iron staining; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Grayish-brown to smoky black with orange iron staining
Luster: Vitreous

Identified July 13, 2026More mineral →

Explore Smoky Quartz (with Iron Inclusions) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed in igneous and metamorphic rocks, specifically pegmatites and hydrothermal veins, through the natural irradiation of aluminum-bearing quartz over millions of years.

Uses & applications

Used in jewelry, decorative ornaments, gemstone collecting, and historically in early sunglasses and optical instruments.

Geological facts

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

Field identification & locations

Look for a translucent to transparent glass-like texture with a smoky tint and a lack of cleavage. Often found near granite outcrops. To identify: it should easily scratch glass but not be scratched by a steel knife.