Sedimentary Rock

Red Jasper (beads)

Silicon Dioxide (SiO2) with iron inclusions

Hardness: 6.5-7 on Mohs scale; Color: typically deep red, brick red, or reddish-brown due to iron impurities; can have patterns, streaks, or spots; Luster: vitreous to dull; Crystal Structure: microcrystalline quartz (chalcedony), massive, no distinct individual crystals visible to the naked eye. Opaque.…

Hardness: 6
Luster: vitreous to dull

Identified November 1, 2025More sedimentary rock →

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Physical properties

Formation & geological history

Red Jasper forms primarily as a chemical sedimentary rock, often precipitated from highly silicic fluids or via the replacement of existing rocks. It's often associated with volcanic activity or hydrothermal alteration, where silica-rich solutions deposit the fine-grained quartz along with iron oxides (hematite) that give it its characteristic red color. Its formation can span various geological ages, frequently found in deposits from the Precambrian to Cenozoic eras.

Uses & applications

Red Jasper is widely used as an ornamental stone and in jewelry manufacturing for beads (as shown), cabochons, carvings, and tumbled stones. Due to its hardness and ability to take a good polish, it's favored for these applications. In construction, larger pieces or slabs might be used for decorative elements, though this is less common than other materials. It is also collected by mineral enthusiasts.

Geological facts

Jasper is a type of chalcedony, which is a microcrystalline variety of quartz. The name 'jasper' itself means 'spotted stone' and is derived from the Old French 'jaspre'. Red Jasper has been used since ancient times for tools, seals, and ornaments. In many cultures, it's believed to have grounding and protective properties.

Field identification & locations

In the field, Red Jasper is identified by its opaque, reddish color, often mottled or patterned. Its hardness can be tested (it will scratch glass). It lacks cleavage and has a conchoidal fracture. It's found worldwide, with significant deposits in countries like India, Russia, Indonesia, Egypt, Australia, and parts of the United States (e.g., Oregon, California, Idaho). For collectors, identifying its characteristic color and patterns, along with its hardness, are key. The beads shown are likely polished and shaped from raw jasper.

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