The slab on the bottom/right came from Marovato and the top/left from Kabamby.) Marovato is on the coast, Kabamby is further inland. The pins in the map above are by their names. (Although all Ocean Jasper® comes from one area in Madagascar, there are actually two different deposits. Polarized light microphotography of Ocean Jasper®, courtesy of Lee Bills, ©2015. Below: Growth interference between orbs, producing irregular polygrams. Middle: Orbs and granular chalcedony and quartz. (Above: Crosscut of an orb, made of fibrous chalcedony with an iron oxide included center. Irregular polygrams are produced where two or more of the orbs touch one another, a formation sometimes seen on a larger scale, especially in material from Kabamby. When thin sections of Ocean Jasper® are examined under a polarized light microscope, the stone is revealed to be fibrous chalcedony spherulites, the flower like patterns, among grains of chalcedony and quartz. Below: Contact between orbs in rough Kabamby Ocean Jasper®, producing irregular polygons.) (Above: A cross cut of a sphere in Kabamby Ocean Jasper®. It is easy to forget that the bulls-eyes, flowers/stars (orbs surrounded by druzy quartz), and irregular polygons are all crosscuts of three dimensional objects. In geology a spherulite is a spherical body, created by radial growth around a central point, like the spokes of a wheel. Spherulitic refers to spherulites, a more technical name for the orbs. He theorized that it is a sphärolithischer Chalcedon (German, “spherulitic or orbicular chalcedony”). The best known research on Ocean Jasper® is by Dr. Polarized light microphotography of Ocean Jasper® courtesy of Becca Hahn, ©2015.)
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