Ocean Jasper

Orbicular Jasper (variety of Chalcedony/Quartz, SiO2)

Rock Type: sedimentary

Ocean Jasper

Physical Properties

Hardness: 6.5-7 (Mohs scale); Color: Variegated greens, white, cream, and brown; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Specific Gravity: 2.6-2.9.

Formation & Geological History

Formed as a result of rhythmic precipitation of silica around a nucleus in volcanic or sedimentary environments. Specifically found in Cretaceous-age rhyolitic flows along the coast of Madagascar.

Uses & Applications

Primarily used for lapidary work, jewelry (cabochons), interior decoration (spheres/carvings), and as a collector's mineral specimen.

Geological Facts

Ocean Jasper is exceptionally rare because the original veins in Madagascar were only accessible by boat at low tide. This specific 'orbicular' pattern is created by the presence of radial clusters of acicular fibers (spherulites).

Field Identification & Locations

Identified by its distinctive multi-colored 'eye' or flower-like orbicular patterns and high hardness. It often contains small druzy quartz-filled vugs. Collectors look for high color contrast and well-defined circles.

Identified on: 4/29/2026

Mode: Standard