Milky Quartz (Water-worn Pebble)
Silicon Dioxide (SiO2)
Rock Type: mineral

Physical Properties
Hardness: 7 on the Mohs scale. Color: Opaque white to creamy tan due to microscopic fluid inclusions. Luster: Vitreous to greasy. Crystal Structure: Trigonal (hexagonal prisms). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.
Formation & Geological History
Formed from silica-rich hydrothermal veins or in igneous pegmatites. This specific specimen has been physically rounded and smoothed by water transport in a river, stream, or beach environment, often over thousands of years.
Uses & Applications
Used as abrasive material, in glassmaking, and as decorative landscaping stone. In metaphysical circles, it is used for 'healing' or meditation. Pure varieties are used in electronics for piezoelectric properties.
Geological Facts
Milky quartz is the most common variety of crystalline quartz. Its white color is caused by tiny bubbles of gas or liquid trapped during the crystal's growth, which scatter light like the water droplets in a cloud.
Field Identification & Locations
Identify in the field by its hardness (it will scratch glass and steel), white color, and lack of cleavage. This rounded shape is a classic 'river rock' indicator. Found globally in almost every geological setting.
Identified on: 4/13/2026
Mode: Standard