mineral

Smoky Quartz with Feldspar

Silicon Dioxide (SiO2) with Potassium Feldspar (KAlSi3O8)

Hardness: 7 (Mohs scale), Color: Smoky grey to brown with reddish-pink inclusions, Luster: Vitreous to dull, Crystal Structure: Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified June 19, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Smoky grey to brown with reddish-pink inclusions, Luster: Vitreous to dull, Crystal Structure: Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed in granitic pegmatites or hydrothermal veins where silicon-rich fluids crystallize. The smoky color is caused by natural irradiation of trace aluminum. Feldspar presence suggests a granitic source rock.

Uses & applications

Used primarily for lapidary work, jewelry making, and as a collector's specimen. Quartz is also used in electronics and glass manufacturing.

Geological facts

The 'smoky' color is actually caused by free silicon formed by irradiation of aluminum impurities. This specimen appears to be a small chunk of pegmatite material, often found near granite outcrops.

Field identification & locations

Identify by its hardness (scratches glass), glass-like luster on fresh surfaces, and lack of cleavage. Look for it in areas with igneous intrusions or gravel beds near mountainous regions.

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