sedimentary

Iron-rich chert or jasper fragment

Microcrystalline quartz (SiO₂), colored by iron oxides/hydroxides

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; reddish-brown to gray, earthy to weakly vitreous luster, opaque, and lacking visible cleavage. The irregular fracture and waxy-looking surfaces are consistent with chalcedonic quartz, while the dark metallic-looking patches may be iron staining or weathering.

Identified August 28, 2026More sedimentary →

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Physical properties

Formation & geological history

Likely formed when silica-rich groundwater replaced or cemented sediment, with iron minerals producing the red-brown coloration; such material commonly ranges from Precambrian to Cenozoic in age. Exact identification requires testing because the image cannot distinguish chert from iron-rich quartzite or a weathered ironstone.

Uses & applications

Used as aggregate, road material, cutting-tool material, and occasionally lapidary rough; attractive pieces may be polished as cabochons or display specimens.

Geological facts

Chert commonly breaks with sharp conchoidal edges and can resemble glassy slag, quartzite, or meteorite fragments. A strong reaction to a steel file, a glass-scratching test, and thin-section or laboratory analysis help confirm it.

Field identification & locations

Common in sedimentary terrains, river gravels, and areas with iron-rich soils worldwide; inspect for uniform microcrystalline texture, conchoidal fracture, and absence of vesicles or bubbles. Avoid assuming it is a meteorite based on dark color alone.