mineral

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Hardness: 7 (Mohs scale); Color: Rusty brown, orange, and gray; Luster: Vitreous to dull/earthy; Crystal Structure: Hexagonal (Trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7 (Mohs scale)
Color: Rusty brown, orange, and gray
Luster: Vitreous to dull/earthy

Identified April 12, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Rusty brown, orange, and gray; Luster: Vitreous to dull/earthy; Crystal Structure: Hexagonal (Trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins or as secondary mineralization where iron-rich fluids permeate existing quartz or silicate rock, often during the oxidation of iron-bearing minerals in sedimentary or metamorphic environments.

Uses & applications

Used primarily as decorative specimens for mineral collectors, lapidary work (cabs or tumbling), and occasionally in metaphysical practices.

Geological facts

Also known as 'Hematoid Quartz' or 'Eisenquartz', the color is caused by microscopic inclusions of hematite or limonite within the quartz crystal structure.

Field identification & locations

Identify in the field by its high hardness (it will scratch glass and steel) and its distinctive rusty staining that does not wash off, unlike surface dirt. Found globally in iron-rich geological regions.

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