"they provide 'crystallized' telltale clues of their environment of formation. Alkali feldspar granite is used as construction material in the form of dimension stones, and polished slabs or tiles for building facades, pavements, and kitchen countertops. Alkali feldspar granite Alkali feldspar granite, some varieties of which are called 'red granite', is a felsic igneous rock and a type of granite rich in the mineral potassium feldspar (K-spar). It is a dense rock with a phaneritic texture. The abundance of K-spar gives the rock a predominant pink to reddish hue; peppered with minor amounts of black minerals. As shown in the"
"Granitoid A granitoid or granitic rock is a variety of coarse grained plutonic rock similar to granite which mineralogically is composed predominantly of feldspar and quartz. Examples of granitoid rocks include granite, quartz monzonite, quartz diorite, syenite, granodiorite, tonalite and trondhjemite. Many are created by continental volcanic arc subduction or the collision of sialic masses. Volcanic rocks are common with granitoids and typically have the same origins. However, they are normally worn away after years of erosion. While many granitoid rocks are located in areas that have experienced crustal thickening during orogenies, others known as ""anorogenic granitoids"" are unrelated to"
"convergent boundaries or subduction zones. These anorogenic granitoids may represent the deep sources for rift volcanism exposed where erosion has removed the volcanic rocks and other evidence of rifting. These ""A-type"" granitoids may have been produced by hotspots or mantle plumes. Granitoid A granitoid or granitic rock is a variety of coarse grained plutonic rock similar to granite which mineralogically is composed predominantly of feldspar and quartz. Examples of granitoid rocks include granite, quartz monzonite, quartz diorite, syenite, granodiorite, tonalite and trondhjemite. Many are created by continental volcanic arc subduction or the collision of sialic masses. Volcanic rocks are common"
"Rock (geology) Rock or stone is a natural substance, a solid aggregate of one or more minerals or mineraloids. For example, granite, a common rock, is a combination of the minerals quartz, feldspar and biotite. The Earth's outer solid layer, the lithosphere, is made of rock. Rock has been used by humankind throughout history. The minerals and metals in rocks have been essential to human civilization. Three major groups of rocks are defined: igneous, sedimentary, and metamorphic. The scientific study of rocks is called petrology, which is an essential component of geology. Rocks are composed of grains of minerals, which"
"Less than that amount would designate the rock as a granite. Other incorporated silicate minerals may include, very minor amounts of plagioclase feldspar, mica in the form of muscovite and/or biotite, and amphibole (often hornblende). Oxide minerals such as magnetite, ilmenite, or ulvospinel. Some sulfides and phosphates (mainly apatite) may also be present. Alkali feldspar granites generally occur with other alkali-rich granitoids, such as monzogranite and syenogranite, forming part of the A-type granites. They are found in a wide range of tectonic settings and their origins remain uncertain. Granitic rocks in general are of interest to geologists, geochemists, etc., because"
"then determined based on the types of minerals present. Schists are foliated rocks that are primarily composed of lamellar minerals such as micas. A gneiss has visible bands of differing lightness, with a common example being the granite gneiss. Other varieties of foliated rock include slates, phyllites, and mylonite. Familiar examples of non-foliated metamorphic rocks include marble, soapstone, and serpentine. This branch contains quartzite—a metamorphosed form of sandstone—and hornfels. The use of rocks has had a huge impact on the cultural and technological development of the human race. Rocks have been used by humans and other hominids for at least"
"of Georgia. The most common rock types in plutons are granite, granodiorite, tonalite, monzonite, and quartz diorite. Generally light colored, coarse-grained plutons of these compositions are referred to as granitoids. The term originated from ""Pluto"", the classical god of the underworld. The use of the name and concept goes back to the beginnings of the science of geology in the late 18th century and the then hotly debated theories of plutonism (or vulcanism), and neptunism regarding the origin of basalt. Pluton In geology, a pluton is a body of intrusive igneous rock (called a plutonic rock) that is crystallized from"
"Arenite Arenite (Latin ""Arena"", sand) is a sedimentary clastic rock with sand grain size between 0.0625 mm (0.00246 in) and 2 mm (0.08 in) and contain less than 15% matrix. The related adjective is ""arenaceous"". The equivalent Greek-derived term is psammite, though this is more commonly used for metamorphosed sediments. Since it refers to grain size rather than chemical composition, the term is used for example in the classification of clastic carbonatic limestones, as the granulometrically equivalent term sandstone is not appropriate for limestone. Other arenites include sandstones, arkoses, greensands, and greywackes. Arenites mainly form by erosion of other rocks"
"than 10% orthoclase, it is called tonalite; pyroxene and amphibole are common in tonalite. A granite containing both muscovite and biotite micas is called a binary or ""two-mica"" granite. Two-mica granites are typically high in potassium and low in plagioclase, and are usually S-type granites or A-type granites. A worldwide average of the chemical composition of granite, by weight percent, based on 2485 analyses: Granite containing rock is widely distributed throughout the continental crust. Much of it was intruded during the Precambrian age; it is the most abundant basement rock that underlies the relatively thin sedimentary veneer of the continents."
"the Carboniferous period, in deltaic conditions. The Millstone Grit Group is a formal stratigraphic term for this sequence of rocks. The gritstone edges of the Peak District are an important climbing area and the rock is much relished by English climbers, among whom it has almost cult status and is often referred to as ""God's own rock"". The rough surface provides outstanding friction, enabling climbers to stand on or grip the subtlest of features in the rock. (See the main article on rock climbing in the Peak District.) Gritstone Gritstone or grit is a hard, coarse-grained, siliceous sandstone. This term"
"Gritstone Gritstone or grit is a hard, coarse-grained, siliceous sandstone. This term is especially applied to such sandstones that are quarried for building material. British gritstone was used for millstones to mill flour, to grind wood into pulp for paper and for grindstones to sharpen blades. ""Grit"" is often applied to sandstones composed of angular sand grains. It may commonly contain small pebbles. ""Millstone Grit"" is an informal term for a succession of gritstones which are to be found in the Peak District and Pennines of northern England. These sediments were laid down in the late (upper) Paleozoic era, in"
"called intrusive or plutonic and cools very slowly, producing a coarse-grained texture such as the rock granite. As a result of volcanic activity, magma (which is called lava when it reaches Earth's surface) may cool very rapidly while being on the Earth's surface exposed to the atmosphere and are called extrusive or volcanic rocks. These rocks are fine-grained and sometimes cool so rapidly that no crystals can form and result in a natural glass, such as obsidian, however the most common fine grained rock would be known as basalt. Any of the three main types of rocks (igneous, sedimentary, and"
"650 °C at a few kBar pressure. Granite has poor primary permeability overall, but strong secondary permeability through cracks and fractures if they are present. Granite is classified according to the QAPF diagram for coarse grained plutonic rocks and is named according to the percentage of quartz, alkali feldspar (orthoclase, sanidine, or microcline) and plagioclase feldspar on the A-Q-P half of the diagram. True granite (according to modern petrologic convention) contains both plagioclase and alkali feldspars. When a granitoid is devoid or nearly devoid of plagioclase, the rock is referred to as alkali feldspar granite. When a granitoid contains less"
"Pikes Peak granite The Pikes Peak granite is a 1.08 billion year old widespread geologic formation found in the central part of the Front Range of Colorado. It is a coarse-grained pink to light red syenogranite with minor gray monzogranite, and it has a distinctive brick-red appearance where it outcrops. The granite gets its name from the Pikes Peak, which is made up almost entirely of this rock. The Pikes Peak granite was emplaced in three major intrusive events in the southern Front Range, now exposed in Colorado's Lost Creek Wilderness, Buffalo Peaks Wilderness, and Pikes Peak. It is the"
"nature of mining processes creates a potential negative impact on the environment both during the mining operations and for years after the mine has closed. This impact has led to most of the world's nations adopting regulations to manage negative effects of mining operations. Rock (geology) Rock or stone is a natural substance, a solid aggregate of one or more minerals or mineraloids. For example, granite, a common rock, is a combination of the minerals quartz, feldspar and biotite. The Earth's outer solid layer, the lithosphere, is made of rock. Rock has been used by humankind throughout history. The minerals"
"or to the English muscovite biotite granite. This application has not been accepted generally. [""This granitic meaning of granulite is now obsolete.""] To the German petrologists granulite means a more or less banded fine-grained metamorphic rock, consisting mainly of quartz and feldspar in very small irregular crystals and usually also containing a fair number of minute, rounded, pale-red garnets. Among English and American geologists the term is generally employed in this sense. The granulites are very closely allied to the gneisses, as they consist of nearly the same minerals, but they are finer-grained, have usually less perfect foliation, are more"
"Ocean. Typically the Deccan Plateau is made up of basalt extending up to Bhor Ghat near Karjat. This is an extrusive igneous rock. Also in certain sections of the region, we can find granite, which is an intrusive igneous rock. The difference between these two rock types is: basalt rock forms on eruption of lava, that is, on the surface (either out of a volcano, or through massive fissures—as in the Deccan basalts—in the ground), while granite forms deep within the Earth. Granite is a felsic rock, meaning it is rich in potassium feldspar and quartz. This composition is continental"
"Decomposed granite Decomposed granite is classification of rock that is derived from granite via its weathering to the point that the parent material readily fractures into smaller pieces of weaker rock. Further weathering yields material that easily crumbles into a mixtures of gravel-sized particles known as grus, that in turn may break down to produce a mixture of clay and silica sand or silt particles. Different specific granite types have differing propensities to weather, and so differing likelihoods of producing decomposed granite. It has practical uses that include its incorporation into paving and driveway materials, residential gardening materials in arid"
"Carbonate rock Carbonate rocks are a class of sedimentary rocks composed primarily of carbonate minerals. The two major types are limestone, which is composed of calcite or aragonite (different crystal forms of CaCO) and dolostone, which is composed of the mineral dolomite (CaMg(CO)). Calcite can be either dissolved by groundwater or precipitated by groundwater, depending on several factors including the water temperature, pH, and dissolved ion concentrations. Calcite exhibits an unusual characteristic called retrograde solubility in which it becomes less soluble in water as the temperature increases. When conditions are right for precipitation, calcite forms mineral coatings that cement the"
"Orbicular granite Orbicular granite (also known as orbicular rock or orbiculite) is an uncommon plutonic rock type which is usually granitic in composition. These rocks have a unique appearance due to ""orbicules"" - concentrically layered, spheroidal structures, probably formed through nucleation around a grain in a cooling magma chamber. Almost one third of known orbicular rock occurrences are from Finland. The occurrences are usually very small. In the Namaqualand, South Africa, just west of the small town of Concordia, there is a rare occurrence of orbicular granite. The outcrop, known as Orbicule Hill or ""wonderkoppie"" (as it is locally known),"
"Rocks State Park is named, is a pile of residual boulders of weathered Graniteville Granite. It is a medium- to coarse-grained, muscovite-biotite alkali granite that, on the average, consists of 55 percent alkali feldspar, 40 percent quartz, and less than 5 percent mafic minerals. The Graniteville Granite is a pluton formed 1.4 billion years ago in the Proterozoic by the cooling of magma that intruded into the volcanic strata and country rock associated with a collapsed caldera. Nearly vertical fractures formed in the stone as it cooled, and uplift of the granite enhanced the fracturing. Eventually the overlying strata were"
"Outcrops of granite tend to form tors and rounded massifs. Granites sometimes occur in circular depressions surrounded by a range of hills, formed by the metamorphic aureole or hornfels. Granite often occurs as relatively small, less than 100 km stock masses (stocks) and in batholiths that are often associated with orogenic mountain ranges. Small dikes of granitic composition called aplites are often associated with the margins of granitic intrusions. In some locations, very coarse-grained pegmatite masses occur with granite. Granite has a felsic composition and is more common in continental crust than in oceanic crust. They are crystallized from felsic"
"occur. One comes from the middle crust and is high in felspar and low in Calcium, and the other kind comes from the lower crust mixed with mantle magmas, and is a calcalkaline granite. The first kind of granite is subdivided into granodiorite and muscovite-biotite leucogranite (two mica granites). The granodiorite can be found at Finisterre, western Salamanca, Zamora, Gredos, Aracena. The two mica leucogranites can be found at Friol, Porto-Viseu, Moncorvo-Vila Real, Vigo, Finisterre, Gil Ibarguchi, La Guardia and also near Salamanca. Most of the granites are 318 Ma to 319 Ma. But some are from 340 Ma. The"
"Calcarenite Calcarenite is a type of limestone that is composed predominantly, more than 50 percent, of detrital (transported) sand-size (0.0625 to 2 mm in diameter), carbonate grains. The grains consist of sand-size grains of either corals, shells, ooids, intraclasts, pellets, fragments of older limestones and dolomites, other carbonate grains, or some combination of these. Calcarenite is the carbonate equivalent of a sandstone. The term calcarenite was originally proposed in 1903 by Grabau as a part of his calcilutite, calcarenite and calcirudite carbonate classification system based upon the size of the detrital grains composing a limestone. Calcarenites can accumulate in a"
"Calcirudite Calcirudite is a type of limestone that is composed predominantly, more than 50 percent, of carbonate grains that are larger in size than sand (2 mm in diameter). The grains can consist of either fragments of fossils, fragments of older limestones and dolomites, other carbonate grains, or some combination of these. The term calcirudite was originally proposed in 1903 by Grabau as a part of his calcilutite, calcarenite and calcirudite classification system based upon the size of the detrital grains composing a limestone. Depending on roundness of the grains, calcirudite is the carbonate equivalent of either a breccia, in"
"Greisen Greisen is a highly altered granitic rock or pegmatite. Greisen is formed by self-generated alteration of a granite and is a class of endoskarn. Greisens appear as highly altered rocks, partly coarse, crystalline granite, partly vuggy with miarolitic cavities, disseminated halide minerals such as fluorite, and occasionally metallic oxide and sulfide ore minerals, borate minerals (tourmaline) and accessory phases such as sphene, beryl or topaz. Greisens are formed by endoskarn alteration of granite during the cooling stages of emplacement. Greisen fluids are formed by granites as the last highly gas- and water-rich phases of complete crystallisation of granite melts."
"Micrite Micrite is a limestone constituent formed of calcareous particles ranging in diameter up to four μm formed by the recrystallization of lime mud. Micrite is lime mud, carbonate of mud grade. In the Folk classification micrite is a carbonate rock dominated by fine-grained calcite. Carbonate rocks that contain fine-grained calcite in addition to allochems are named ""intramicrite"", ""oomicrite"", ""biomicrite"" or ""pelmicrite"" under the Folk classification depending on the dominant allochem. Micrite as a component of carbonate rocks can occur as a matrix, as micrite envelopes around allochems or as peloids. Micrite can be generated by chemical precipitation, from disaggregation"
"Rhyolite Rhyolite is an igneous, volcanic rock, of felsic (silica-rich) composition (typically > 69% SiO – see the TAS classification). It may have any texture from glassy to aphanitic to porphyritic. The mineral assemblage is usually quartz, sanidine and plagioclase (in a ratio > 2:1 – see the QAPF diagram). Biotite and hornblende are common accessory minerals. It is the extrusive equivalent to granite. Rhyolite can be considered as the extrusive equivalent to the plutonic granite rock, and consequently, outcrops of rhyolite may bear a resemblance to granite. Due to their high content of silica and low iron and magnesium"
"Greywacke Greywacke or graywacke (German ""grauwacke"", signifying a grey, earthy rock) is a variety of sandstone generally characterized by its hardness, dark color, and poorly sorted angular grains of quartz, feldspar, and small rock fragments or lithic fragments set in a compact, clay-fine matrix. It is a texturally immature sedimentary rock generally found in Paleozoic strata. The larger grains can be sand- to gravel-sized, and matrix materials generally constitute more than 15% of the rock by volume. The term ""greywacke"" can be confusing, since it can refer to either the immature (rock fragment) aspect of the rock or its fine-grained"
"or turbiditic re-deposition of sands. Some arenites contain a varying amount of carbonatic components and thus belong to the rock-category of carbonatic sandstones or silicatic limestones. Arenites often appear as massive or bedded medium-grained rocks with a middling- to wide-spaced preferred lamination and often develop a pronounced cleavage. Pettijohn gives the following descriptive terms based on grain size, avoiding the use of terms such as ""clay"" or ""argillaceous"" which carry an implication of chemical composition: Arenite Arenite (Latin ""Arena"", sand) is a sedimentary clastic rock with sand grain size between 0.0625 mm (0.00246 in) and 2 mm (0.08 in) and"
"A-type granite A-type granites are a class of granite. They are characterised by low water and a lack of tectonic fabric. A stands for anorogenic or anhydrous. The granite class was proposed by Loiselle and Wones in 1979. It was in addition to I-, S- and M-type granites. The A-type granites form in an extensional tectonic setting. This could either be far from any orogeny, or after orogeny is completed. Chemical characteristics of A-type granites include high silica, alkalis, zirconium, niobium, gallium, yttrium and cerium. The ratio of gallium to aluminium is high, as is the ratio of iron to"
"quartz in the latter case. Other rocks can be defined by relative abundances of key (essential) minerals; a granite is defined by proportions of quartz, alkali feldspar, and plagioclase feldspar. The other minerals in the rock are termed accessory, and do not greatly affect the bulk composition of the rock. Rocks can also be composed entirely of non-mineral material; coal is a sedimentary rock composed primarily of organically derived carbon. In rocks, some mineral species and groups are much more abundant than others; these are termed the rock-forming minerals. The major examples of these are quartz, the feldspars, the micas,"
"Aplite Aplite () is an intrusive igneous rock in which the mineral composition is the same as granite, but in which the grains are much finer, under 1 mm across. Quartz and feldspar are the dominant minerals. The term 'aplite' or 'aplitic' is often used as a textural term to describe veins of quartz and feldspar with a fine to medium-grain ""sugary"" texture. Aplites are usually very fine-grained, white, grey or pinkish, and their constituents are visible only with the help of a magnifying lens. Dykes and veins of aplite are commonly observed traversing granitic bodies; they occur also, though"