mineral

Quartz with Iron Staining

Silicon Dioxide (SiO2) with iron oxide impurities

Hardness: 7 on Mohs scale; Color: Clear to white with brown/orange staining; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Clear to white with brown/orange staining
Luster: Vitreous (glassy)

Identified April 26, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes or within pegmatites where silica-rich fluids crystallize. The orange/brown coloring comes from secondary iron oxide staining (limonite or hematite) following the crystal's formation.

Uses & applications

Quartz is used in glassmaking, electronics (piezoelectric properties), and abrasives. Iron-stained specimens are primarily collected by hobbyists or used for decorative yard stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Iron-stained quartz is often mistaken for gold by novice prospectors due to the metallic-looking brown sheen and host rock association.

Field identification & locations

Identify by its ability to scratch glass and lack of cleavage. Look for glassy luster on fractured surfaces. Very common in mountainous regions, riverbeds, and weathered outcrops globally.

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