mineral

Quartz (Milky or Smoky)

Silicon Dioxide (SiO2)

7 on Mohs scale, waxy to vitreous luster, hexagonal crystal system (though massive here), conchoidal fracture, white to tan/yellowish hue due to iron staining or inclusions, specific gravity 2.65.

Identified July 14, 2026More mineral →

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Physical properties

7 on Mohs scale, waxy to vitreous luster, hexagonal crystal system (though massive here), conchoidal fracture, white to tan/yellowish hue due to iron staining or inclusions, specific gravity 2.65.

Formation & geological history

Forms in hydrothermal veins or as a late-stage crystallization in igneous rocks like granite. This specimen appears water-worn or weathered, likely found in a riverbed or alluvial deposit.

Uses & applications

Industrial use in glassmaking, abrasives, and electronics. Common in jewelry as a gemstone and highly sought after by mineral collectors for its various forms.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is piezoelectric, meaning it can generate an electric charge when mechanical stress is applied.

Field identification & locations

Identify in the field by its hardness (will scratch glass) and lack of cleavage. Look for a greasy luster on freshly broken surfaces. Common worldwide in gravel pits, beaches, and mountain outcrops.