mineral

Quartz (with Iron staining)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Luster: Vitreous to waxy

Identified May 3, 2026More mineral →

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Physical properties

Formation & geological history

Formed via hydrothermal activity where silica-rich fluids cool in igneous or metamorphic host rocks. The staining occurs due to later exposure to iron-rich groundwater or oxidation of secondary minerals.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, and as a collector's specimen for lapidary work.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'Quarz', which has Slavic origins meaning 'hard'.

Field identification & locations

Identify in the field by its ability to scratch glass and lack of cleavage. Found globally in riverbeds, mountains, and desert pavements. This specific specimen shows alluvial wear (rounded edges).