sedimentary

Jasper

Silicon dioxide (SiO2)

Hardness: 6.5-7 (Mohs); Color: tan, yellow, orange-ish; Luster: vitreous to waxy; Structure: cryptocrystalline quartz; Cleavage: none (conchoidal fracture).

Hardness: 6
Color: tan, yellow, orange-ish
Luster: vitreous to waxy

Identified April 13, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs); Color: tan, yellow, orange-ish; Luster: vitreous to waxy; Structure: cryptocrystalline quartz; Cleavage: none (conchoidal fracture).

Formation & geological history

Formed from silica-rich fluids circulating through volcanic ash or sedimentary layers. This process of petrification or chemical precipitation occurs over millions of years, typically during the Cretaceous to Tertiary periods.

Uses & applications

Commonly used as a gemstone, for lapidary work (cabs and beads), decorative ornaments, and healing crystals in various cultures.

Geological facts

Jasper is an opaque variety of chalcedony. It takes such a high polish that it has been used historically for making seals and vases in ancient Mediterranean civilizations.

Field identification & locations

Identify by its high hardness (won't be scratched by a steel knife) and its smooth, waxy feel. Often found in riverbeds, coastal gravels, or desert regions worldwide, particularly in the western USA (Oregon, Idaho).