mineral

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 Mohs; Color: White to tan/yellowish (due to iron staining); Luster: Vitreous to waxy; Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7 Mohs
Color: White to tan/yellowish (due to iron staining)
Luster: Vitreous to waxy

Identified June 11, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: White to tan/yellowish (due to iron staining); Luster: Vitreous to waxy; Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Formation & geological history

Formed primarily in hydrothermal veins and pegmatites. This specific specimen is a water-worn river pebble, likely transported and eroded over thousands of years to its rounded shape.

Uses & applications

Industrial use in glassmaking, abrasives, and electronics (piezoelectric properties). Often used as decorative landscaping stone or as a base material in construction.

Geological facts

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

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and waxy luster when rounded. Common in riverbeds, beaches, and gravel pits worldwide. Collectors should look for unique inclusions or iron banding.