Quartz Pebble
Silicon Dioxide (SiO2)
Rock Type: mineral

Physical Properties
Hardness: 7 on Mohs scale; Color: Off-white/Gray/Translucent; Luster: Vitreous to dull (weathered); Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65
Formation & Geological History
Formed from cooling magma or hydrothermal veins. This specific specimen is likely water-worn or mechanically weathered from a larger quartz vein, often found in alluvial deposits or glacial till.
Uses & Applications
Used in glassmaking, electronics (piezoelectric properties), abrasives, and as construction aggregate. Smooth pebbles are often used in landscaping or as pocket stones.
Geological Facts
Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'Quarz' and is highly resistant to chemical and physical weathering.
Field Identification & Locations
Identify by its hardness (will scratch glass) and lack of cleavage. Commonly found in riverbeds, beaches, and soil. To identify, look for a waxy or glassy luster underneath the weathered exterior.
Identified on: 5/10/2026
Mode: Standard