sedimentary
Ocean Jasper
Orbicular Jasper (Silicon Dioxide with impurities like Hematite and Chlorite, SiO2)
Hardness: 6.5-7 (Mohs scale), Color: Variegated greens, creams, and dark spots with orbicular (eye-like) patterns, Luster: Vitreous to waxy, Crystal Structure: Trigonal (Microcrystalline), Cleavage: None
- Hardness
- 6
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Physical properties
Hardness: 6.5-7 (Mohs scale), Color: Variegated greens, creams, and dark spots with orbicular (eye-like) patterns, Luster: Vitreous to waxy, Crystal Structure: Trigonal (Microcrystalline), Cleavage: None
Formation & geological history
Formed through the precipitation of silica from volcanic fluids in gas cavities or rhyolitic flows, often found in tidal regions. Most high-quality specimens date to the Cenozoic era.
Uses & applications
Primarily used for lapidary work, jewelry, ornamental carvings, and as a popular specimen for mineral collectors and metaphysical practitioners.
Geological facts
Ocean Jasper is specifically found along the coast of Madagascar. It is unique because it can only be mined at low tide by boat; many of the original veins have already been depleted.
Field identification & locations
Identify by its distinctive orbicular 'eyelike' circles and flow-patterned colors. Unlike regular jasper, it often contains druzy quartz pockets. Common in coastal Madagascar outcrops.
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