Web1. feb 2009 · Spherulites are spherical clusters of radiating crystals that occur naturally in rhyolitic obsidian. The growth of spherulites requires diffusion and uptake of crystal …
(PDF) Timescales of spherulite crystallization in obsidian inferred ...
Web1. nov 2008 · We measured water concentration profiles around spherulites in obsidian by synchrotron Fourier transform infrared spectroscopy. The distribution of OH - groups … Spherulites are most common in silica-rich glassy rocks. Sometimes they compose the whole mass; more usually they are surrounded by a glassy or felsitic base. When obsidians are devitrified, the spherulites are often traceable, though they may be more or less completely recrystallized or silicified. In the center of a … Zobraziť viac In petrology, spherulites 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 … Zobraziť viac Under the microscope the spherulites are of circular outline and are composed of thin divergent fibers that are crystalline as verified with polarized light. Between crossed Zobraziť viac Very large and cavernous spherulites are called lithophysae; they are found in obsidians at Lipari, in Yellowstone Park and other places. The characteristic radiate fibrous structure … Zobraziť viac Variolites are a type of radiate fibrous growth, resembling spherulites in many respects, consisting of minute feathery crystals spreading outwards through a fine grained or glassy rock. In variolites there are straight or feathery feldspar crystals (usually Zobraziť viac Occasionally spherulites are found that are many centimeters and, even more rarely, up to two or three meters in diameter. Those … Zobraziť viac Artificial glass sometimes crystallizes and contains spherulites that may be as large as a marble. As the glass has little similarity in chemical composition to volcanic … Zobraziť viac hsl hinta
Spherulite Aspect In The Obsidian Lava Flow From …
Web2. nov 2007 · Spherulites are spherical clusters of radiating crystals that occur naturally in rhyolitic obsidian. The growth of spherulites requires diffusion and uptake of crystal forming components from the host rhyolite melt or glass, and rejection of non-crystal forming components from the crystallizing region. Web20. jún 2024 · L'obsidienne flocon de neige est connue comme une pierre de pureté. Ce cristal est censé purifier et équilibrer votre corps, votre cœur, votre esprit et votre esprit. Il agit en vous débarrassant des toxines qui bloquent la libre circulation des énergies positives. La pierre est également idéale pour dessiner des émotions et des ... WebSpherulites that manifest concentric shells are called orbicules and are found in some granites and syenites. The shells have different mineralogies and in orbicular granite and granodiorite the bulk composition differs … hsl hinnat 2021