Granite (pronounced /ˈɡrænɪt/) is a common and widely occurring type of intrusive An intrusion is any formation of intrusive igneous rock; rock formed from magma that cools and solidifies within the crust of a planet. In contrast, an extrusion consists of extrusive rock; rock formed above the surface of the crust, felsic Felsic is a term used in geology to refer to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. The term combines the words "feldspar" and "silica." Felsic minerals are usually light in color and have specific gravities less than 3. Common, igneous Igneous rock is one of the three main rock types (the others being sedimentary and metamorphic rock). Igneous rock is formed by magma (molten rock) cooling and becoming solid. Igneous rock may form with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks. This magma can rock In geology, rock is a naturally occurring solid aggregate of minerals and/or mineraloids. Granites usually have a medium to coarse grained texture. Occasionally some individual crystals (phenocrysts A phenocryst is a relatively large and usually conspicuous crystal distinctly larger than the grains of the rock groundmass of a porphyritic igneous rock. Phenocrysts often have euhedral forms either due to early growth within a magma or by post-emplacement recrystallization) are larger than the groundmass The matrix or groundmass of rock is the fine-grained mass of material in which larger grains or crystals are embedded in which case the texture is known as porphyritic Rock microstructure includes the texture of a rock and the small scale rock structures. The words "texture" and "microstructure" are interchangeable, with the latter preferred in modern geological literature. However, texture is still acceptable because it is a useful means of identifying the origin of rocks, how they formed,. A granitic rock with a porphyritic texture is sometimes known as a porphyry Porphyry is a variety of igneous rock consisting of large-grained crystals, such as feldspar or quartz, dispersed in a fine-grained feldspathic 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. Granites can be pink to dark gray or even black, depending on their chemistry and mineralogy. Outcrops An outcrop is an exposure of bedrock or superficial deposits[citation needed] at the surface of the Earth of granite tend to form tors A tor is a rock outcrop formed by weathering, usually found on or near the summit of a hill. In the South West of England, where the term originated, it is also a word used for the hills themselves – particularly the high points of Dartmoor in Devon and Bodmin Moor in Cornwall, and rounded massifs In geology, a massif is a section of a planet's crust that is demarcated by faults or flexures. In the movement of the crust, a massif tends to retain its internal structure while being displaced as a whole. The term is also used to refer to a group of mountains formed by such a structure. In mountaineering and climbing literature, a massif is. Granites sometimes occur in circular depressions Depression in geology is a landform sunken or depressed below the surrounding area. Depressions may be formed by various mechanisms, and may be referred to by a variety of technical terms surrounded by a range of hills, formed by the metamorphic aureole Metamorphism is the solid-state recrystallization of pre-existing rocks due to changes in physical and chemical conditions, primarily heat, pressure, and the introduction of chemically active fluids. Mineralogical, chemical and crystallographic changes can occur during this process or hornfels Hornfels is the group designation for a series of contact metamorphic rocks that have been baked and indurated by the heat of intrusive igneous masses and have been rendered massive, hard, splintery, and in some cases exceedingly tough and durable. Most hornfels are fine-grained, and while the original rocks (such as sandstone, shale and slate,.
Granite is nearly always massive (lacking internal structures), hard and tough, and therefore it has gained widespread use as a construction stone. The average density The density of a material is defined as its mass per unit volume. The symbol of density is ρ of granite is 2.75 g/cm3 and its viscosity at standard temperature and pressure is ~4.5 • 1019 Pa·s.[1]
The word granite comes from the Latin Latin is an Italic language originally spoken in Latium and Ancient Rome. With the Roman conquest, Latin was spread to countries around the Mediterranean, including a large part of Europe. Romance languages, such as Aragonese, Corsican, Catalan, French, Italian, Portuguese, Romanian, and Spanish, are descended from Latin, while many others, granum, a grain, in reference to the coarse-grained structure of such a crystalline A crystal or crystalline solid is a solid material, whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is crystallography. The process of crystal formation via mechanisms of crystal growth is called rock.
Granitoid is used as a discriptive field term for general, light colored, coarse-grained igneous rocks for which a more specific name requires petrographic Petrography is that branch of petrology which focuses on detailed descriptions of rocks. Someone who studies petrography is called a petrographer. The mineral content and the textural relationships within the rock are described in detail. Petrographic descriptions start with the field notes at the outcrop and include megascopic description of hand examination.[2]
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