mineral

Ferruginous Quartz (Red Quartz)

Silicon Dioxide with Iron Oxide inclusions (SiO2 + Fe2O3)

AI-generated identification · may be incorrect

Hardness: 7 on the Mohs scale. Color: Translucent grayish-pink to reddish-brown with iron-rich earthy patches. Luster: Vitreous to waxy. Crystal structure: Trigonal/Hexagonal. Cleavage: None, exhibits conchoidal fracture. Specific gravity: 2.65.

Hardness: 7 on the Mohs scale
Luster: Vitreous to waxy

Identified July 26, 2026More mineral →

Explore Ferruginous Quartz (Red Quartz) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed in silica-rich hydrothermal veins or sedimentary environments where quartz crystallized in the presence of iron oxide minerals like hematite or goethite. Often naturally tumbled and smoothed by stream or beach action.

Uses & applications

Popular among rock collectors and lapidary hobbyists for tumbling, polishing, and crafting decorative stone items.

Geological facts

The reddish coloration in ferruginous quartz comes from hematite or iron oxide coatings and fractures within the quartz crystal lattice, giving it a rusty or brownish-pink hue.

Field identification & locations

Identified by its ability to scratch glass (Mohs 7), translucent quartz body, and reddish-brown hematite inclusions or staining. Commonly found along riverbeds, gravel bars, and glacial deposits worldwide.