mineral

Ocean Jasper

Spherulitic Chalcedony (SiO2)

Hardness: 6.5-7 (Mohs scale); Color: Polychromatic (green, brown, pink, yellow); Luster: Vitreous to waxy; Structure: Microcrystalline (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.65

Hardness: 6
Color: Polychromatic (green, brown, pink, yellow)
Luster: Vitreous to waxy

Identified March 20, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed through the infiltration of silica-rich fluids into volcanic rhyolite flows, creating orbicular (circular) mineral deposits. Primarily found in deposits in the Marovato region of Madagascar, typically dating to the Cretaceous period.

Uses & applications

Primarily used for lapidary work, jewelry (cabochons), ornamental carvings, and as highly sought-after specimens for geological collections and metaphysical practitioners.

Geological facts

Ocean Jasper is only found on the coast of Madagascar and can only be mined at low tide. Despite its name, it is technically a form of chalcedony rather than a true jasper, which is typically opaque and contains more iron impurities.

Field identification & locations

Identify in the field by its distinct orbicular (eye-like) patterns and varied colors. It is found in remote coastal areas of Madagascar. Collectors look for high contrast in colors and well-defined 'eyes' or druzy quartz pockets.