sedimentary

Ocean Jasper (Orbicular Jasper)

Silicon Dioxide (SiO2) with iron and other impurities

Hardness: 6.5-7 (Mohs); Color: Multicolored with spots/circles (green, orange, red, brown); Luster: Vitreous to waxy; Crystal Structure: Cryptocrystalline (Trigonal); Cleavage: None; Specific Gravity: 2.58-2.91

Hardness: 6
Color: Multicolored with spots/circles (green, orange, red, brown)
Luster: Vitreous to waxy

Identified April 25, 2026More sedimentary →

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Physical properties

Formation & geological history

Ocean Jasper is a variety of chalcedony that formed through volcanic activity where silica-rich fluids cooled and solidified in flows of rhyolite or tuff. The orbicular patterns were created as circular structures called spherulites grew within the cooling rock.

Uses & applications

Primarily used for lapidary work, jewelry making (cabochons), interior decoration (polished points/spheres), and as a popular semi-precious stone for mineral collectors.

Geological facts

Ocean Jasper is highly unique because the only known deposit is located on the coast of Madagascar and can only be accessed by boat at low tide. No two pieces are exactly alike due to the chaotic nature of the orbicular patterns.

Field identification & locations

Identify by its distinctive 'eyes' or circular orb patterns embedded in a solid matrix. While most abundant in Madagascar, similar orbicular jasper can be found in small pockets elsewhere. Collectors should look for high color contrast and spherical pattern clarity.

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