mineral

Milky Quartz with Iron Inclusions

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white with brown/red iron Oxide stains; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white with brown/red iron Oxide stains
Luster: Vitreous to greasy

Identified March 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of magma or hydrothermal activity in veins. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth. Iron oxides (like hematite or goethite) seep into micro-fractures over time.

Uses & applications

Used in glassmaking, abrasives, and as a common gemstone for tumbled stones or 'worry stones'. High-grade quartz is used in electronics and clocks due to its piezoelectric properties.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is often found alongside gold in hydrothermal vein deposits, leading many prospectors to use it as an indicator mineral.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife and its lack of cleavage. It is commonly found in riverbeds as water-worn pebbles or in outcropping veins. It is a 'beginner' stone found nearly worldwide.

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