sedimentary

Red jasper (likely iron-stained chert)

Microcrystalline quartz, SiO₂, colored chiefly by iron oxides; identification is provisional from the photo

AI-generated identification · may be incorrect

Opaque, brick-red to reddish-brown with pale patches and a small dark area; dull to slightly waxy luster and irregular fracture. Quartz hardness is about 7 Mohs; no visible cleavage, and the material is too fine-grained to show crystals.

Identified September 28, 2026More sedimentary →

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Physical properties

Formation & geological history

Jasper forms when silica-rich sediment or volcanic material becomes silicified, with iron oxides supplying the red color. Such deposits occur in rocks of many geological ages.

Uses & applications

Attractive jasper is cut and polished for beads, cabochons, carvings, and ornamental objects; jasper-rich material may also be used as decorative stone.

Geological facts

Jasper is an opaque variety of chalcedony, itself a microcrystalline form of quartz. Red coloration commonly comes from hematite or related iron oxides.

Field identification & locations

Look for opaque, consistently fine-grained material, red or brown coloration, and a hard, conchoidal-to-irregular fracture; a scratch test and closer examination would help distinguish jasper from other iron-stained rocks. Found worldwide, often in silica-rich sedimentary or volcanic settings.