mineral

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide inclusions (Hematite/Limonite)

Hardness: 7 on Mohs scale; Color: Reddish-brown, orange, or rusty pink due to iron staining; Luster: Vitreous (glassy) to waxy; Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Reddish-brown, orange, or rusty pink due to iron staining
Luster: Vitreous (glassy) to waxy

Identified March 8, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes or within sedimentary environments where groundwater rich in iron silica precipitates. The iron inclusions create the distinct red-to-orange hue. This specific specimen appears to be a water-worn or weathered pebble found in alluvial deposits or glacial till.

Uses & applications

Used primarily for lapidary work (cabochons, beads), decorative landscaping stone, and as metaphysical 'healing' crystals. High-purity quartz is also used in glassmaking and electronics.

Geological facts

Also known as 'Eisenkiesel' in German (meaning iron pebble), these stones have been used since antiquity for charms and talismans. The color is often superficial or concentrated in cracks, but can also be uniformly distributed throughout the crystal lattice.

Field identification & locations

Identify in the field by its hardness (will scratch glass easily), translucent to opaque appearance, and distinctive rusty color that does not wash off. Commonly found in riverbeds, gravel pits, and mountain runoff areas worldwide.

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