sedimentary

Jasper (Red and Yellow Jasper)

SiO2 (Silicon Dioxide) with Iron Oxide inclusions

AI-generated identification · may be incorrect

Hardness: 6.5-7.0 (Mohs scale), Color: Variegated red, yellow, and brown, Luster: Vitreous to dull, Crystal structure: Microcrystalline/Cryptocrystalline, Cleavage: None (Conchoidal fracture), Specific gravity: 2.6-2.9

Hardness: 6

Identified June 19, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed via the deposition of silica from water-rich environments or hydrothermal solutions, often in volcanic or sedimentary beds. The coloration is primarily due to iron oxide impurities (Hematite for red, Goethite for yellow).

Uses & applications

Used extensively in jewelry as cabochons or beads, ornamental decor, lapidary arts, and stone tool making in ancient times.

Geological facts

Jasper is a variety of chalcedony. It is completely opaque, unlike its cousin Agate which is translucent. It has been used for seals and amulets since the Mycenaean civilization.

Field identification & locations

Identify by its hardness (cannot be scratched by a steel knife), opaque nature, and smooth, waxy feel when wet. Commonly found in riverbeds, gravel pits, and desert washes.