Milky Quartz with Iron Staining

Physical Properties

Hardness: 7 (Mohs scale); Color: White to orange-brown (iron-stained); Luster: Vitreous to waxy; 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; the orange coloration is due to the secondary oxidation of iron-bearing minerals (limonite/hematite) on the surface or within fractures.

Uses & Applications

Used as a source of silica for glassmaking, abrasive in sandblasting, decorative landscaping, and occasionally as a minor gemstone while tumbled.

Geological Facts

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

Field Identification & Locations

Identify by its hardness (scratches glass), lack of cleavage, and waxy luster. Common globally in river beds, beaches, and mountainous regions as float or vein material.

Identified on: 5/11/2026

Mode: Standard