mineral

Quartz (Iron-Stained / Yellow Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Pale yellow to orange-brown due to iron oxide staining. Luster: Vitreous to greasy. Crystal System: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific Gravity: ~2.65.

Hardness: 7 on Mohs scale
Color: Pale yellow to orange-brown due to iron oxide staining
Luster: Vitreous to greasy

Identified July 23, 2026More mineral →

Explore Quartz (Iron-Stained / Yellow 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

Forms in a wide range of geological environments, including hydrothermal veins, igneous pegmatites, and metamorphic rocks. Iron oxides deposit into micro-fractures, giving it a yellow or rusty appearance.

Uses & applications

Used as a gemstone, decorative specimen, lapidary material, and historically in glassmaking and electronics.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Iron staining can occur naturally via groundwater carrying iron minerals into tiny surface cracks.

Field identification & locations

Identified by its glass-like vitreous/greasy luster, inability to be scratched by a steel blade, and lack of cleavage. Found worldwide in riverbeds, pegmatites, and gravel deposits.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Sandstone with Mineral Veining or Crust

Sedimentary Sandstone (mostly SiO2 with Fe2O3 tinting)

sedimentary

Potassium Feldspar (Orthoclase)

Orthoclase (KAlSi3O8)

mineral

Gypsum (variety Selenite or Alabaster)

Calcium sulfate dihydrate (CaSO4·2H2O)

Mineral

Nephrite Jade

Nephrite

Mineral/Rock