mineral

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Tan to reddish-brown due to iron oxide impurities; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Tan to reddish-brown due to iron oxide impurities
Luster: Vitreous to greasy

Identified July 5, 2026More mineral →

Explore Quartz (Iron-stained) 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 from silica-rich hydrothermal fluids or within igneous and metamorphic rocks. This specific piece shows signs of weathering and iron-staining from groundwater contact.

Uses & applications

Used widely in manufacturing glass, electronics (piezoelectric properties), and as decorative gravel or landscaping stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is clear, but iron oxides can tint it yellow, orange, or brown, sometimes mimicking the appearance of citrine.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and translucent appearance. It is found globally in riverbeds, mountains, and beaches.