
sedimentary
Iron-rich breccia (likely hematite–goethite breccia)
Hematite (Fe₂O₃) and goethite (FeO(OH)) in a silicified or iron-cemented breccia
AI-generated identification · may be incorrectHardness varies about 5–6.5 Mohs; rusty red, orange-brown, gray-black; typically earthy to metallic or submetallic luster. Irregular angular fragments and porous, massive texture are visible; specific gravity commonly ~3–5, depending on iron content.
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Physical properties
Hardness varies about 5–6.5 Mohs; rusty red, orange-brown, gray-black; typically earthy to metallic or submetallic luster. Irregular angular fragments and porous, massive texture are visible; specific gravity commonly ~3–5, depending on iron content.
Formation & geological history
Forms when iron-rich hydrothermal fluids or weathering processes precipitate oxides and hydroxides in fractures, cementing broken rock. Such deposits range from ancient Precambrian iron formations to much younger supergene weathering zones.
Uses & applications
Used as iron ore where sufficiently concentrated, and occasionally as pigment, lapidary material, or a collector specimen; generally unsuitable for aggregate if highly porous or friable.
Geological facts
Hematite commonly produces a distinctive red-to-reddish-brown streak, while goethite may form yellow-brown powder. The specimen’s orange matrix and dark metallic patches strongly suggest oxidized iron minerals, though exact identification requires streak, hardness, and ideally analytical testing.
Field identification & locations
Common in iron-ore districts, gossans, hydrothermal veins, and weathered mineral deposits worldwide. Test an inconspicuous spot for a red-brown streak; a magnet may show weak attraction if magnetite is also present.
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