mineral

Quartz (White or Milky Quartz Pebble)

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to greyish; Luster: Vitreous (glassy) to waxy when tumbled; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to greyish
Luster: Vitreous (glassy) to waxy when tumbled

Identified February 5, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich hydrothermal veins or within igneous pegmatites. This specific specimen is a water-worn or tumbled pebble, indicating post-formation erosion and transport in a river or coastal environment.

Uses & applications

Used widely in manufacturing glass, electronics (piezoelectric properties), and as decorative stones or gemstones. Tumbled pieces are common in 'worry stones' or crystal healing collections.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its clouded appearance from tiny fluid inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify by its ability to scratch glass and lack of cleavage. Commonly found in riverbeds, beaches, and mountain trails globally. Collectors should look for translucency and smooth texture in tumbled pieces.

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