Rock Identifier
Milky Quartz Pebble (Quartz (SiO2) with fluid inclusions) — mineral
mineral

Milky Quartz Pebble

Quartz (SiO2) with fluid inclusions

Hardness: 7 (Mohs scale); Color: Opaque white to cream with faint yellow staining; Luster: Vitreous to waxy (especially when water-worn); Crystal structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness
7 (Mohs scale)
Color
Opaque white to cream with faint yellow staining
Luster
Vitreous to waxy (especially when water-worn)
Identified More mineral
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Physical properties

Hardness: 7 (Mohs scale); Color: Opaque white to cream with faint yellow staining; Luster: Vitreous to waxy (especially when water-worn); Crystal structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed from hydrothermal veins or as a primary constituent of igneous rocks. This specific specimen has been rounded and smoothed by water erosion (alluvial or beach transport) over thousands of years.

Uses & applications

Used as decorative landscaping gravel, in glassmaking, and as a component in construction materials. Polished specimens are used in jewelry and crystal healing practices.

Geological facts

The milky white appearance comes from microscopic bubbles of gas or liquid trapped within the crystal as it grew, which scatter light and prevent transparency.

Field identification & locations

Identify by its hardness (it can scratch glass), lack of cleavage, and smooth, frosted surface when found in riverbeds or beaches. Found globally where quartz-rich rocks are subject to erosion.