mineral

Quartz with Iron Staining

Silicon Dioxide (SiO2) with Hematite inclusions

Hardness: 7 (Mohs scale), Color: Smoky/white with reddish-brown staining, Luster: Vitreous to greasy, Crystal structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified May 7, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal fluids or cooling magma. The reddish staining is caused by secondary oxidation of iron-bearing minerals (hematite/goethite) leaching into cracks and surfaces over geological time.

Uses & applications

Common quartz is used in glassmaking, electronics, and as an abrasive. Specimens like this are primarily of interest to hobbyist collectors or used as landscaping material.

Geological facts

Quartz is one of the most abundant minerals in Earth's crust. The red 'rust' color on this specimen is actually a thin coating of iron oxide, which can often be removed with a mild acid bath if desired by collectors.

Field identification & locations

Identify in the field by its ability to scratch glass and lack of cleavage. It is commonly found in riverbeds, mountains, and desert pavements worldwide. Look for the distinctive conchoidal (glass-like) fracture patterns on broken faces.

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