mineral

Ferruginous Quartz

Silicon Dioxide with Iron Oxide Inclusions (SiO2)

Hardness of 7 on the Mohs scale; color ranges from clear to white, stained with yellow, orange, and reddish-brown iron oxides (limonite or hematite); vitreous luster; trigonal crystal system; conchoidal fracture with no true cleavage; specific gravity of 2.65.

Identified August 4, 2026More mineral →

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Physical properties

Formation & geological history

Forms in hydrothermal veins, pegmatites, and sedimentary environments where silicon-rich solutions crystallize, often with iron-rich fluids infiltrating fractures and coating or penetrating the crystal structure over geological time.

Uses & applications

Used in mineral collecting, lapidary arts, making decorative items, and occasionally as a semi-precious gemstone.

Geological facts

Quartz is one of the most abundant minerals on Earth's continental crust. The reddish and yellowish hues in this specimen are caused by iron staining, which is very common in weathered surface deposits.

Field identification & locations

Easily identified by its high hardness (scratches glass), lack of cleavage, and characteristic rusty iron staining. Found worldwide in pegmatites, river gravels, and vein deposits.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Soil with Mineral Detritus and Quartz Fragments

Regolith / Silicate Mineral Aggregate

sedimentary

Limonite / Goethite (Iron Ore Mineral nodule)

FeO(OH)·nH2O / FeO(OH)

mineral

Septarian Pebble

Septarian nodule / Concretion

sedimentary

Schist

Metamorphic

Potassium Feldspar (Orthoclase)

Orthoclase (KAlSi3O8)

mineral