Mineral

Quartz with Limonite Staining

Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)

Hardness: 7 (Quartz) and 4-5.5 (Limonite); Color: Grayish-white with yellow-brown staining; Luster: Vitreous to dull; Crystal structure: Trigonal/Amorphous; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65.

Hardness: 7 (Quartz) and 4-5
Color: Grayish-white with yellow-brown staining
Luster: Vitreous to dull

Identified April 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or as a secondary alteration product. Limonite staining occurs when iron-bearing minerals oxidize in the presence of water (weathering).

Uses & applications

Common quartz is used for glassmaking and abrasives. Iron-stained specimens like this are primarily of interest to amateur collectors or as fill material in construction.

Geological facts

Limonite is not a single mineral but a mixture of hydrated iron oxide minerals like goethite. It often 'paints' quartz crystals a golden or rusty color, which collectors sometimes call 'Golden Healer' in metaphysical circles.

Field identification & locations

Identify in the field by checking if the yellow color is a surface coating or internal staining on a hard, glass-like host rock. Commonly found in areas with high iron content and quartz outcroppings.

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