mineral

Milky Quartz with Mineral Inclusions

Quartz (Silicon Dioxide - SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to translucent with grey/black mineral veining; Luster: Vitreous (glassy) to waxy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Opaque white to translucent with grey/black mineral veining
Luster: Vitreous (glassy) to waxy

Identified March 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in veins or pegmatites within the Earth's crust. It can be found in rocks of all geological ages, often weather-released into riverbeds as water-worn pebbles.

Uses & applications

Used in the production of glass, ceramics, and electronics (due to piezoelectric properties). In this pebble form, it is common in landscaping, decorative gravel, and for beginner lapidary/rock tumbling.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The 'milky' appearance is caused by tiny fluid inclusions of gas or liquid trapped during the crystal's growth.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (hardness 7) and its lack of cleavage. This specific specimen shows 'druzy' or massive texture with dark inclusions, likely manganese or iron oxides. Commonly found in riverbeds, beaches, and mountain trails worldwide.

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