Porphyry (geology) - Wikipedia Porphyry ( ˈpɔːrfəri POR-fə-ree) is any of various 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
What Is Porphyry? How Does It Form, and In Which Rocks? Porphyry is a textural term that describes any intrusive or extrusive igneous rock with consistently larger crystals set in a finer-grained matrix Metamorphic rocks showing such a texture are known as porphyroblasts
Porphyry (geology) - New World Encyclopedia Porphyry is a variety of igneous rock consisting of large-grained crystals, such as feldspar or quartz, dispersed in a fine-grained feldspathic [1] matrix or groundmass
Porphyry Deposits - Geology Science Porphyry deposits are formed through a combination of geological processes that take place over long periods of time These processes include magmatism, hydrothermal activity, and the interaction of mineral-rich fluids with the surrounding rock
Porphyry | geological feature | Britannica (A porphyry is an igneous rock containing conspicuous crystals, called phenocrysts, surrounded by a matrix of finer-grained minerals or glass or both ) In most rocks, both alkali and plagioclase feldspars occur as irregularly shaped grains with only a few or no crystal faces
Porphyry – Imperial Stone of the Roman Empire | Select Stone Porphyry is an igneous rock similar in composition to granite Unlike common granites, pophyry has large, light-colored crystals of quartz or feldspar floating in a red or purple fine-grained matrix of smaller crystals
GemRocks: Porphyry - Central Michigan University DESCRIPTION: Porphyry is the term geologists apply to igneous rocks that consist of relatively large grains or crystals, called phenocrysts, surrounded by a finer grained material, usually called the groundmass