mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: Creamy white with grey inclusions, Luster: Vitreous to waxy, Crystal structure: Hexagonal (microcrystalline in this form), Cleavage: None, Specific gravity: 2.65

Identified May 11, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Creamy white with grey inclusions, Luster: Vitreous to waxy, Crystal structure: Hexagonal (microcrystalline in this form), Cleavage: None, Specific gravity: 2.65

Formation & geological history

Formed through crystallization of silica-rich fluids in hydrothermal veins or as a secondary mineral in various rock types. This specific specimen has been rounded and smoothed by water erosion (fluvial or beach processes) over hundreds to thousands of years.

Uses & applications

Commonly used in construction (aggregate), glass making, and as an abrasive. Polished pebbles are often used in landscaping, aquariums, and decorative stone crafts.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. These small water-worn pebbles are often called 'omars' or 'river stones' depending on their specific geological history and location.

Field identification & locations

Identified by its hardness (will scratch glass), lack of cleavage, and smooth, rounded surface from water wear. Found globally in riverbeds, beaches, and glacial deposits. For collectors, these serve as introductory specimens to mineralogy.