Is Porphyry Granite

Porphyry is an igneous rock similar in composition to granite.

Is porphyry granite.

Petrographic examination is required for identification of specific types of granitoids. Porphyry is an igneous rock that contains larger crystals phenocrysts in a fine grained groundmass. Hardness of granite and porphyry is 6 7. It s a type of granite that has naturally extruded through the earth s crust.

Porphyry copper deposits and read more. Granite is a light colored igneous rock with grains large enough to be visible with the unaided eye. Porphyry is a textural term for an igneous rock consisting of large 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 refers to the purple red form of this stone valued for its appearance. The romans used it because it had a naturally flat durable surface and the stone was easy to quarry.

K feldspar phenocrysts in this sample. The word porphyry comes from the latin word for purple which was the color of nobility to the romans. Granite is available in black grey orange pink white colors whereas porphyry is available in black brown colourless green grey red rust white colors. The extrusive igneous rock equivalent of granite is rhyolite.

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. Porphyry is a diversity of igneous rock consisting of large grained crystal such as quartz and feldspar scattered in a fine grained groundmass. It forms from the slow crystallization of magma below earth s surface. Traditional porphyry is a variable thickness stone.

Properties of rock is another aspect for granite vs porphyry. Porphyry is an igneous rock characterized by porphyritic texture. Granite is composed mainly of quartz and feldspar with minor amounts of mica amphiboles and other minerals this mineral composition usually gives granite a red pink gray or white color with dark mineral. Porphyritic texture is a very common texture in igneous rocks in which larger crystals phenocrysts are embedded in a fine grained groundmass.

Porphyritic refers to the texture of the rocks. A granitic rock with a porphyritic texture is known as a granite porphyry. The groundmass is composed of indistinguishable crystals aphanites as in basalt or easily distinguishable crystals phanerites as in granite. Among the most distinctive hydrothermal deposits is a class known as porphyry copper deposits so called because they are invariably associated with igneous intrusives that are porphyritic meaning the rock is a mixture of coarse and fine mineral grains.

Granitoid is a general descriptive field term for lighter colored coarse grained igneous rocks.