mineral

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Clear to gray with red/orange iron oxidation; Luster: Vitreous (glassy); Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Clear to gray with red/orange iron oxidation
Luster: Vitreous (glassy)

Identified March 8, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Clear to gray with red/orange iron oxidation; Luster: Vitreous (glassy); Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through hydrothermal processes where silica-rich fluids cool in veins, or as a primary mineral in igneous rocks. The red staining is caused by secondary hematite or goethite (iron oxides) leaching into cracks from surrounding soil or water.

Uses & applications

Industrial uses include glassmaking and electronics (piezoelectric properties). In the state shown, it is primarily used as aggregate for construction or a base-level specimen for hobbyist collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'quarz', which originally meant 'hard'. Iron-stained quartz is often called 'Ferruginous Quartz' in a mineralogical context.

Field identification & locations

Identify in the field by its inability to be scratched by a steel blade, its glassy appearance, and its lack of cleavage planes (it breaks like glass). Commonly found in riverbeds, mountains, and desert landscapes worldwide.