mineral

Milky Quartz (Water-worn pebble/nodule)

Quartz (Silicon Dioxide - SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to cream due to fluid inclusions; Luster: Vitreous to waxy (when weathered); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to cream due to fluid inclusions
Luster: Vitreous to waxy (when weathered)

Identified March 20, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal fluids or within igneous pegmatites. This specific specimen’s rounded, pitted texture suggests it was eroded from a vein and tumbled in a high-energy environment like a riverbed or shoreline for thousands of years.

Uses & applications

Milky quartz is used as a source of silicon for semiconductors, in glassmaking, as decorative landscaping stone, and occasionally in rough jewelry or as healing crystals in metaphysical practices.

Geological facts

Quartz is the most abundant mineral in the Earth's continental crust. The 'milky' appearance is caused by tiny bubbles of gas or liquid trapped during the crystal's growth, which scatter light.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (H=5.5) and its lack of cleavage plane. It is found globally, particularly in areas with metamorphic or igneous bedrock. Look for the 'greasy' luster on freshly broken surfaces.

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