sedimentary

Red jasper (likely iron-rich chert)

Microcrystalline quartz (SiO₂), colored mainly by hematite/goethite impurities

AI-generated identification · may be incorrect

Opaque brick-red to maroon, dull to slightly waxy luster, very fine-grained and massive; Mohs hardness about 6.5–7, no cleavage, conchoidal fracture, and specific gravity around 2.6. The white patches may be quartz or calcite veining, while dark areas may contain iron oxides or manganese minerals.

Identified September 22, 2026More sedimentary →

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Physical properties

Formation & geological history

Forms when silica-rich sediment or volcanic-derived fluids cement and replace fine sediment, with iron oxides producing the red color; ages range from Precambrian to recent depending on locality. This specimen may also be iron-rich silicified volcanic rock rather than pure jasper.

Uses & applications

Used as an ornamental and lapidary stone for cabochons, carvings, beads, countertops, and polished slabs; common pieces have modest collecting value.

Geological facts

Its red color is typically caused by dispersed hematite rather than copper. Jasper is a variety of chert, but field identification should be confirmed by hardness, streak, and thin-section or chemical testing.

Field identification & locations

Common in iron-rich sedimentary and volcanic terrains worldwide, including India, Brazil, Madagascar, Australia, and the western United States. It should resist scratching by a steel knife and may scratch glass; avoid relying on color alone.