According to the Perceived Service Quality model (Figure 1), the quality of a service, as perceived by the customer, is the result of a comparison between the expectations of the customer and his or her real-life experiences.
Resorption of garnet I may have occurred either as a result of the prograde univariant reaction Grt + Chl + Ms = St + Bt + Qtz + H2O, or during decompression, by the net transfer reaction Grt + Ms + H2O = St + Bt + Qtz, before staurolite had become unstable.
Obsidian Rock Facts. Obsidian is an igneous rock that forms when molten rock cools very rapidly. The result is a rock that cooled so fast, crystals did not get a chance to form. Obsidian is a volcanic glass with a smooth and uniform structure. Interesting Obsidian Rock Facts:Different varieties of obsidian rock get their names from their appearance.bsidian is also known as nature's glass because of its glassy appearance. When obsidian breaks, the fractures are very sharp which is why it was used as tools in the Stone Age. Seventy percent of obsidian rock is made of silica. Obsidian can only form near active volcanoes.