The following information is extracted from The Book of Stones and other sources:
Ocean Jasper is an unusual jasper variety found only in Madagascar. Like other jaspers, it is a member of the quartz family, a silicon dioxide mineral with a hardness of 6.5 to 7. Its colors vary widely, including vivid shades of white, green, pink, red and black. The cavities in Ocean Jasper are often filled with sparkling druzy quartz.
From heartofstone.com: "Ocean Jasper is a rare mineral, mined in only one place in the world, the Mine of Marovato, on the Ambolobozo Peninsula in the the north west corner of Madagascar. Is called Ocean Jasper because the deposits are part of the coastline, and can only be reached by boat, and removed only during low tide. This stone is immediately recognizable by its concentric rings of color, earning at the name "Orbicular Ocean Jasper." The most common shades are greens and whites, with the less common shades of pinks and yellows also appearing in some specimens."
In The Book of Stones Robert Simmons calls it a stone of joy and high spirits. It is a wonderful healing stone.
Below are a few of the Ocean Jasper stones I have wrapped.