Milky Quartz (Stained with Iron)
Silicon Dioxide (SiO2)
Rock Type: mineral

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.
Identified on: 4/21/2026
Mode: Standard