sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Hardness of 6.5-7 on the Mohs scale, colors vary widely (red, brown, yellow, green) due to iron and other mineral impurities, waxy to vitreous luster, cryptocrystalline structure, conchoidal fracture with no cleavage, specific gravity of 2.58-2.91.

Identified August 6, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the silification of sedimentary rocks or volcanic ash, where silica-rich fluids replace original materials over millions of years. Often found in ancient marine environments, hydrothermal veins, and sedimentary deposits.

Uses & applications

Used for making jewelry, ornamental carvings, decorative objects, and as a popular specimen for rock tumbling and lapidary arts.

Geological facts

Jasper has been used by ancient civilizations since antiquity for tools, seals, and amulets. It is mentioned in various historical texts and was favored by ancient Minoans, Greeks, and Romans.

Field identification & locations

Identified easily by its opaque nature, hardness, and lack of cleavage with a smooth conchoidal fracture. Found worldwide, particularly in regions with significant volcanic or sedimentary activity such as India, Russia, Brazil, and the USA.