Quartz (specifically Quartzite or Massive Quartz)

Physical Properties

Hardness: 7 (Mohs scale), Color: Tan to watery white, Luster: Vitreous to waxy, Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & Geological History

Formed through the crystallization of magma or from hydrothermal veins. This specific specimen appears to be a 'river rock' or 'alluvial pebble' that has been smoothed and rounded by water erosion over long periods.

Uses & Applications

Quartz is used in glassmaking, electronics (piezoelectric properties), abrasives, and as semi-precious gemstones in jewelry. These smoothed pebbles are often used in landscaping or for lapidary tumbling.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. It is chemically very stable and resistant to weathering, which is why it often remains as pebbles long after other minerals have eroded away.

Field Identification & Locations

Identify in the field by its hardness (it will scratch glass and steel) and its lack of cleavage. Look for the smooth, rounded texture and 'waxy' appearance typical of water-worn quartz. Found globally in river beds and beaches.

Identified on: 4/27/2026

Mode: Standard