Porphyry is the name given to decorative granites or igneous rocks with coarse-grained crystals such as feldspar or quartz dispersed in a fine-grained silicate-rich, generally aphanitic matrix or groundmass. The larger crystals are called phenocrysts. In its non-geologic, traditional use, the term porphyry usually refers to the purple-red form of this stone, valued for its appearance, but other colours of decorative porphyry are also used such as "green", "black" and "grey". WebJun 24, 2005 · A. Porphyry. "Chinese writing stone [or rock]" (height of egg - 6.1 cm) from unspecified locality in California. Claude Pelisson's collection. (© ... Light transmission - opaque except for those with glass …
Porphyry - an overview ScienceDirect Topics
WebDec 31, 2014 · An illustration of a magnifying glass. An illustration of a magnifying glass. An illustration of a horizontal line over an up pointing arrow. Upload An illustration of a ... A. … WebPorphyry is an igneous rock that contains larger crystals (phenocrysts) in a fine-grained groundmass. K-feldspar phenocrysts in this sample. Width of view 7 cm. TUG 1608-2807. It seems simple enough but unfortunately … nothing puzzles god
Collection Search Corning Museum of Glass
WebJewel-like colors streamed to the altar from stained-glass windows to fall on this and other precious ... a Fatimid rock crystal flask, and a porphyry vase from Egypt or imperial Rome that he fitted with gilded mounts to create a … WebThe porphyritic texture is a type of texture occurring in volcanic and intrusive igneous rocks defined by the presence of larger crystals, called phenocrysts, surrounded by a matrix of … WebThese rocks are intruded by a quartz monzonite porphyry stock and by numerous breccia masses, which contain fragments of all the older rock types. southernperu.com. ... Glass … nothing quiet