sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2)

Hardness: 6.5-7 on Mohs scale; Color: Yellow, brown, and ochre; Luster: Dull to vitreous; Crystal Structure: Microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Hardness: 6
Color: Yellow, brown, and ochre
Luster: Dull to vitreous

Identified May 16, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Yellow, brown, and ochre; Luster: Dull to vitreous; Crystal Structure: Microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Formation & geological history

Formed from silica-rich fluids in volcanic ash or sedimentary environments where minerals like iron oxides leach into the silica during the cooling or lithification process. It is often found in prehistoric deposits ranging from millions to billions of years old.

Uses & applications

Commonly used for lapidary work, jewelry (cabochons), ornamental decoration, and as a healing stone in metaphysical communities. Historically used for making tools and weapons due to its hardness.

Geological facts

The word 'Jasper' is derived from the Greek for 'spotted stone'. It is an opaque variety of chalcedony. Many ancient civilizations, including the Egyptians and Sumerians, used it for seals and amulets.

Field identification & locations

Identify in the field by its opacity (even on thin edges), smooth conchoidal fracture, and ability to scratch glass. Found worldwide, frequently in river beds or desert areas. Collectors look for unique patterns and color transitions.