mineral

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Milky white to tan with orange/brown iron oxide staining
Luster: Vitreous (glassy) to greasy

Identified June 6, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes or cooling of silica-rich magma/lava. Often found in veins or as a major constituent in granite and pegmatites. This specimen likely formed in a hydrothermal vein and has been exposed to iron-rich groundwater.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), abrasives, and as a semi-precious gemstone in jewelry or for decorative collection.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Iron staining occurs when hematite or limonite particles are trapped on the surface or in micro-cracks, giving it a 'rusty' appearance.

Field identification & locations

Identify in the field by its hardness (it can scratch glass and steel), lack of cleavage, and waxy/glassy appearance. Found globally in almost all geological environments, especially in mountain ranges and riverbeds.