mineral

Smoky Quartz (Ferruginous Quartz)

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Brownish-gold to smoky grey with iron oxide staining; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Brownish-gold to smoky grey with iron oxide staining
Luster: Vitreous (glassy) to greasy

Identified April 12, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or pegmatites from cooling silica-rich solutions. The brownish-yellow staining is likely due to 'limonite' or iron oxide coatings from environmental weathering.

Uses & applications

Used in gemstone lapidary, aesthetic collection, and industrial electronics or glass-making if pure. Commonly used as metaphysical 'healing' stones.

Geological facts

Quartz is one of the most abundant minerals in Earth's crust. This specific piece shows significant ferruginous (iron) staining, which often gives common quartz a golden or rusty 'Citrine-like' appearance.

Field identification & locations

Identify by its glassy luster, lack of cleavage, and inability to be scratched by a steel knife. Commonly found in gardens, gravel pits, and mountain ranges.

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