mineral

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified April 7, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed from silica-rich hydrothermal veins or within igneous and metamorphic rocks. This specific specimen is a water-worn river stone or beach pebble, shaped by erosion over centuries to millennia.

Uses & applications

Used in landscaping, glass manufacturing, electronics (due to piezoelectric properties), and as decorative stones for aquariums or vase filler.

Geological facts

Milky quartz gets its cloudy appearance from microscopic inclusions of fluid (gas or liquid) that were trapped when the crystal was forming.

Field identification & locations

Identify in the field by its hardness (it will scratch glass) and its lack of cleavage. Common in riverbeds, glacial tills, and beaches worldwide. It is one of the most abundant minerals on Earth.