mineral

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white with orange/yellow iron staining (limonite); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white with orange/yellow iron staining (limonite)
Luster: Vitreous to greasy

Identified April 12, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal solutions or as a primary constituent of igneous and metamorphic rocks. This specific specimen appears to be a water-worn or weathered cobble, potentially from a riverbed or glacial deposit.

Uses & applications

Industrial uses include glassmaking, electronics (piezoelectric properties), and abrasives. In this form, it is primarily a decorative garden stone or a low-level collector specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The yellow/orange tint is not inherent to the crystal structure but is a surface coating or infusion of iron oxide minerals like goethite or limonite.

Field identification & locations

Identify in the field by its hardness (it will scratch glass and steel), lack of cleavage, and waxy/vitreous luster. Common worldwide in almost all geological environments.