mineral

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Luster: Vitreous to greasy

Identified May 3, 2026More mineral →

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Physical properties

Formation & geological history

Formed from hydrothermal veins or as a late-stage mineral in igneous pegmatites. This specimen likely weathered out of a larger quartz vein. The yellow-orange tint comes from external iron-rich groundwater seeping into micro-fractures.

Uses & applications

Used in the production of glass, ceramics, and electronics (as a source of silicon). In jewelry, it is used for cabochons or beads. Also used extensively as a decorative landscape stone.

Geological facts

Quartz is the most abundant mineral in the Earth's continental crust. Specimens like this one, showing heavy staining, are often called 'Gold Quartz' by casual prospectors, though the color usually comes from iron, not actual gold.

Field identification & locations

Identify in the field by its hardness (will scratch glass and steel) and lack of cleavage. Found globally in almost all geological environments. This specific specimen appears to be water-worn, likely found on a beach or in a riverbed.

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