mineral

Milky Quartz (Stained with Iron)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to Tan/Yellow (iron-stained); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White to Tan/Yellow (iron-stained)
Luster: Vitreous to greasy

Identified April 21, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to Tan/Yellow (iron-stained); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed from the cooling of silica-rich hydrothermal fluids in veins or pegmatites; common throughout various geological ages from Precambrian to recent.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, and as a landscaping stone/collector specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Iron-stained quartz like this is often mistakenly called 'Citrine,' though true Citrine is colored by heat/radiation rather than surface oxidation.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and translucent properties. Often found in riverbeds, mountain outcrops, and garden fill.

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Mineral/Rock

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