sedimentary

Ocean Jasper

Spherulitic Chalcedony (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale); Color: Polychromatic circles or 'eyes' in shades of green, brown, pink, and white; Luster: Vitreous to waxy; Structure: Microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.60-2.65.

Hardness: 6
Luster: Vitreous to waxy

Identified March 29, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed by the precipitation of silica in rhythmic bands or spherules within volcanic rock cavities. Specifically found in rhythmically deposited sedimentary-like layers within the shorelines of Madagascar.

Uses & applications

Predominantly used for lapidary arts, jewelry, meditation stones, and decorative sculptures such as the 'flame' carving shown in the image.

Geological facts

Ocean Jasper is only found in one location worldwide: the coast of Madagascar. It can only be mined during low tide, earning it its aquatic name. It is technically a variety of chalcedony rather than a true jasper.

Field identification & locations

Identify by its distinctive orbicular (circular) patterns and 'flower' like inclusions. In the field, look for opaque volcanic rocks with multicolored circles. Collectors should look for high color contrast and well-defined 'eyes'.