mineral

Milky or Iron-Stained Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale. Color: Translucent white to milky, with yellowish-orange 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 March 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes, crystallization from cooling magma (igneous), or as a secondary precipitate in sedimentary environments. Quartz is chemically stable and persists long after parent rocks erode. This specimen appears water-worn or tumbled.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), abrasive materials, jewelry, and popular as 'pocket stones' for crystal collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is clear, but impurities like iron give it the yellow/orange rusty hue seen here, often called 'Liminitic Quartz'.

Field identification & locations

Identify in the field by its hardness (it will scratch glass and metal) and lack of cleavage. Commonly found in riverbeds, gravel pits, and mountain ranges globally. Collectors should look for waxy translucency and resistance to scratching.

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