mineral

Quartz / Iron-Stained Quartz

Silicon Dioxide (SiO2) with iron oxide inclusions/staining

Hardness: 7 on Mohs scale; Color: Milky white to translucent with brown/yellow iron staining; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to translucent with brown/yellow iron staining
Luster: Vitreous to greasy

Identified April 12, 2026More mineral →

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Physical properties

Formation & geological history

Formed from hydrothermal veins or as a secondary mineral in igneous and metamorphic environments. This piece shows signs of alluvial weathering, indicating it was likely transported by water before being found.

Uses & applications

Common quartz is used in construction as aggregate, in glass manufacturing, and in electronics for its piezoelectric properties. This specific specimen serves as a collector's field find.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Iron-stained quartz like this is often referred to by gold prospectors as 'rusty quartz', which can sometimes indicate the presence of lode gold in the area.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife and its lack of cleavage. It is commonly found in riverbeds, mountains, and desert washes globally. Collectors should look for crystalline structures or associated minerals like pyrite.

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