Spheres composed of needles or rods, all oriented perpendicular to the outer surface, or a plane section through such a sphere. A common form of polymer crystallization from melts or concentrated...

Spherulites, in petrology, are small, rounded bodies that commonly occur in vitreous igneous rocks. They are often visible in specimens of obsidian, pitchstone and rhyolite as globules about the size of millet seed or rice grain, with a duller luster...