mineral

Smoky Quartz Geode

Silicon Dioxide (SiO2)

Hardness: 7; Color: Translucent grey to brown; Luster: Vitreous; Crystal Structure: Trigonal (hexagonal prisms); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7
Color: Translucent grey to brown
Luster: Vitreous

Identified June 26, 2026More mineral →

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Physical properties

Hardness: 7; Color: Translucent grey to brown; Luster: Vitreous; Crystal Structure: Trigonal (hexagonal prisms); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the slow crystallization of silica-rich hydrothermal fluids within cavities (vugs) in host rocks. The smoky color is caused by natural irradiation of trace aluminum during or after crystal growth. Common in the Appalachian orogenic zones of Eastern Canada.

Uses & applications

Used primarily for spiritual practices, gem collecting, jewelry (faceted or cabochon), and as decorative display specimens.

Geological facts

The smoky tint is often a result of proximity to radioactive minerals in the crust, though the crystals themselves are safe. In Quebec and the Gaspe Peninsula, quartz veins are common results of ancient volcanic and tectonic activity.

Field identification & locations

Identify by its hexagonal crystal terminations inside a cavity and its signature grey-brown transparency. Found in many areas of the Canadian Shield and Appalachian regions of Quebec. Look for it in weathered rock outcrops or stream beds.