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76-717: On the Kösseine rises an eponymous stream (officially called the Kössein ), which flows through Waldershof and Marktredwitz before discharging into the Rösla , a tributary of the Ohře , near Seußen. In the vicinity of the Große Kösseine peak is a large granite blockfield with an area of 15.8 hectares (39 acres) which has been placed under protection. Various rock formations (the Kleine Kösseine,

152-420: A completely crystalline rock. Granitic rocks mainly consist of feldspar , quartz , mica , and amphibole minerals , which form an interlocking, somewhat equigranular matrix of feldspar and quartz with scattered darker biotite mica and amphibole (often hornblende ) peppering the lighter color minerals. Occasionally some individual crystals ( phenocrysts ) are larger than the groundmass , in which case

228-553: A basaltic magma to a granitic magma, but the quantities produced are small. For example, granitic rock makes up just 4% of the exposures in the South Sandwich Islands . In continental arc settings, granitic rocks are the most common plutonic rocks, and batholiths composed of these rock types extend the entire length of the arc. There are no indication of magma chambers where basaltic magmas differentiate into granites, or of cumulates produced by mafic crystals settling out of

304-786: A common public water supply and waste water treatment facility. Following the war, Waldershof invested millions of German Marks (DM) in the infrastructure. The 1993 founded bicycle manufacturer CUBE is headquartered in Waldershof. CUBE sells their products into 60 countries. Waldershof is known for their numerous clubs and associations, provide many opportunities for sport and social encounters in every city precinct. The city has 8 volunteer fire departments. Zeitler, Walther. (Ed.). (1988). Heimatbuch der Stadt Waldershof. Amberg, Bavaria, Germany: Vereinigte Oberpfaelzische Druckereien und Verlagsanstalt Gmbh, Translated by: Walter Swett Granite Granite ( / ˈ ɡ r æ n ɪ t / GRAN -it )

380-520: A diapir it would expend far too much energy in heating wall rocks, thus cooling and solidifying before reaching higher levels within the crust. Fracture propagation is the mechanism preferred by many geologists as it largely eliminates the major problems of moving a huge mass of magma through cold brittle crust. Magma rises instead in small channels along self-propagating dykes which form along new or pre-existing fracture or fault systems and networks of active shear zones. As these narrow conduits open,

456-509: A few (known as leucogranites ) contain almost no dark minerals. Granite is nearly always massive (lacking any internal structures), hard (falling between 6 and 7 on the Mohs hardness scale) , and tough. These properties have made granite a widespread construction stone throughout human history. The word "granite" comes from the Latin granum , a grain, in reference to the coarse-grained structure of such

532-610: A granite that is derived from partial melting of metasedimentary rocks may have more alkali feldspar, whereas a granite derived from partial melting of metaigneous rocks may be richer in plagioclase. It is on this basis that the modern "alphabet" classification schemes are based. The letter-based Chappell & White classification system was proposed initially to divide granites into I-type (igneous source) granite and S-type (sedimentary sources). Both types are produced by partial melting of crustal rocks, either metaigneous rocks or metasedimentary rocks. I-type granites are characterized by

608-565: A high content of sodium and calcium, and by a strontium isotope ratio, Sr/ Sr, of less than 0.708. Sr is produced by radioactive decay of Rb, and since rubidium is concentrated in the crust relative to the mantle, a low ratio suggests origin in the mantle. The elevated sodium and calcium favor crystallization of hornblende rather than biotite. I-type granites are known for their porphyry copper deposits. I-type granites are orogenic (associated with mountain building) and usually metaluminous. S-type granites are sodium-poor and aluminum-rich. As

684-820: A much higher proportion of clay with the Cecil soil series a prime example of the consequent Ultisol great soil group. Granite is a natural source of radiation , like most natural stones. Potassium-40 is a radioactive isotope of weak emission, and a constituent of alkali feldspar , which in turn is a common component of granitic rocks, more abundant in alkali feldspar granite and syenites . Some granites contain around 10 to 20 parts per million (ppm) of uranium . By contrast, more mafic rocks, such as tonalite, gabbro and diorite , have 1 to 5 ppm uranium, and limestones and sedimentary rocks usually have equally low amounts. Many large granite plutons are sources for palaeochannel -hosted or roll front uranium ore deposits , where

760-536: A peculiar mineralogy and geochemistry, with particularly high silicon and potassium at the expense of calcium and magnesium and a high content of high field strength cations (cations with a small radius and high electrical charge, such as zirconium , niobium , tantalum , and rare earth elements .) They are not orogenic, forming instead over hot spots and continental rifting, and are metaluminous to mildly peralkaline and iron-rich. These granites are produced by partial melting of refractory lithology such as granulites in

836-568: 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 forms from silica-rich ( felsic ) magmas. Felsic magmas are thought to form by addition of heat or water vapor to rock of

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912-415: A result, they contain micas such as biotite and muscovite instead of hornblende. Their strontium isotope ratio is typically greater than 0.708, suggesting a crustal origin. They also commonly contain xenoliths of metamorphosed sedimentary rock, and host tin ores. Their magmas are water-rich, and they readily solidify as the water outgasses from the magma at lower pressure, so they less commonly make it to

988-466: Is grus , which is often made up of coarse-grained fragments of disintegrated granite. Climatic variations also influence the weathering rate of granites. For about two thousand years, the relief engravings on Cleopatra's Needle obelisk had survived the arid conditions of its origin before its transfer to London. Within two hundred years, the red granite has drastically deteriorated in the damp and polluted air there. Soil development on granite reflects

1064-539: Is microgranite . The extrusive igneous rock equivalent of granite is rhyolite . Granitic 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. Outcrops of granite tend to form tors , domes or bornhardts , and rounded massifs . Granites sometimes occur in circular depressions surrounded by

1140-517: Is 3–6·10 Pa·s. The melting temperature of dry granite at ambient pressure is 1215–1260 °C (2219–2300 °F); it is strongly reduced in the presence of water, down to 650 °C at a few hundred megapascals of pressure. Granite has poor primary permeability overall, but strong secondary permeability through cracks and fractures if they are present. A worldwide average of the chemical composition of granite, by weight percent, based on 2485 analyses: The medium-grained equivalent of granite

1216-557: Is a blue granite that is unique in Europe, is also called Kleinwendern Granite or Schurbach Granite and occurs near Schurbach and Kleinwendern . It also occurs in a narrow band at the Luisenburg Rock Labyrinth north of the Kösseine that runs eastwards. Only the eastern part of the lower rock labyrinth consists of Kösseine Granite, the western part is made of Dach Granite. Kösseine Granite is quarried today only near Waldershof in

1292-480: Is a coarse-grained ( phaneritic ) intrusive igneous rock composed mostly of quartz , alkali feldspar , and plagioclase . It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions . These range in size from dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers. Granite

1368-543: Is about 15 cm. The first documented reference to the town of “Waltershove” can be found in a certificate from July 1, 1263, that was written in Latin. The certificate is part of the registry of deeds from the Waldsassen monastery and is currently preserved in the main city archives of Munich. This document shows Count Friedrich von Leuchtenberg (bei Weiden/Opf.), with the agreement of his brother Gebhardt, transferred ownership of

1444-410: Is an excess of aluminum beyond what can be taken up in feldspars (Al 2 O 3 > CaO + K 2 O + Na 2 O) are described as peraluminous , and they contain aluminum-rich minerals such as muscovite . The average density of granite is between 2.65 and 2.75 g/cm (165 and 172 lb/cu ft), its compressive strength usually lies above 200 MPa (29,000 psi), and its viscosity near STP

1520-618: Is believed to have a mass of around 81 tonnes. It was the tallest temple in south India. Imperial Roman granite was quarried mainly in Egypt, and also in Turkey, and on the islands of Elba and Giglio . Granite became "an integral part of the Roman language of monumental architecture". The quarrying ceased around the third century AD. Beginning in Late Antiquity the granite was reused, which since at least

1596-556: Is bounded on the North by the City of Marktredwitz. The boundary line between the two cities is also the border for the counties of Tirschenreuth and Wunsiedel as well as the regional zones of the Upper Palatinate and Upper Franconia. Since the completion of the municipality reform, the population has grown to approximately 5,000 inhabitants. Due to their locations, the unincorporated portions of

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1672-434: 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, as described below . Another aspect of granite classification is the ratios of metals that potentially form feldspars. Most granites have a composition such that almost all their aluminum and alkali metals (sodium and potassium) are combined as feldspar. This

1748-433: Is limited by the amount of thermal energy available, which must be replenished by crystallization of higher-melting minerals in the magma. Thus, the magma is melting crustal rock at its roof while simultaneously crystallizing at its base. This results in steady contamination with crustal material as the magma rises. This may not be evident in the major and minor element chemistry, since the minerals most likely to crystallize at

1824-404: Is permeated by sheets and channels of light granitic rock (the leucosome ). The leucosome is interpreted as partial melt of a parent rock that has begun to separate from the remaining solid residue (the melanosome). If enough partial melt is produced, it will separate from the source rock, become more highly evolved through fractional crystallization during its ascent toward the surface, and become

1900-454: Is relieved when overlying material is removed by erosion or other processes. Chemical weathering of granite occurs when dilute carbonic acid , and other acids present in rain and soil waters, alter feldspar in a process called hydrolysis . As demonstrated in the following reaction, this causes potassium feldspar to form kaolinite , with potassium ions, bicarbonate, and silica in solution as byproducts. An end product of granite weathering

1976-411: Is some concern that some granite sold as countertops or building material may be hazardous to health. Dan Steck of St. Johns University has stated that approximately 5% of all granite is of concern, with the caveat that only a tiny percentage of the tens of thousands of granite slab types have been tested. Resources from national geological survey organizations are accessible online to assist in assessing

2052-479: Is that magma will rise through the crust as a single mass through buoyancy . As it rises, it heats the wall rocks , causing them to behave as a power-law fluid and thus flow around the intrusion allowing it to pass without major heat loss. This is entirely feasible in the warm, ductile lower crust where rocks are easily deformed, but runs into problems in the upper crust which is far colder and more brittle. Rocks there do not deform so easily: for magma to rise as

2128-410: Is the case when K 2 O + Na 2 O + CaO > Al 2 O 3 > K 2 O + Na 2 O. Such granites are described as normal or metaluminous . Granites in which there is not enough aluminum to combine with all the alkali oxides as feldspar (Al 2 O 3 < K 2 O + Na 2 O) are described as peralkaline , and they contain unusual sodium amphiboles such as riebeckite . Granites in which there

2204-485: Is typical of a larger family of granitic rocks , or granitoids , that are composed mostly of coarse-grained quartz and feldspars in varying proportions. These rocks are classified by the relative percentages of quartz, alkali feldspar, and plagioclase (the QAPF classification ), with true granite representing granitic rocks rich in quartz and alkali feldspar. Most granitic rocks also contain mica or amphibole minerals, though

2280-409: Is typically orthoclase or microcline and is often perthitic . The plagioclase is typically sodium-rich oligoclase . Phenocrysts are usually alkali feldspar. Granitic rocks are classified according to the QAPF diagram for coarse grained plutonic rocks and are named according to the percentage of quartz , alkali feldspar ( orthoclase , sanidine , or microcline ) and plagioclase feldspar on

2356-428: Is uncommon, is classified simply as quartz-rich granitoid or, if composed almost entirely of quartz, as quartzolite . True granites are further classified by the percentage of their total feldspar that is alkali feldspar. Granites whose feldspar is 65% to 90% alkali feldspar are syenogranites , while the feldspar in monzogranite is 35% to 65% alkali feldspar. A granite containing both muscovite and biotite micas

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2432-463: Is unique to this region and has Alpine characteristics. Area's near or in the forest are sometimes not snow-free until the middle of May. Giant snowdrifts and severe snow storms render paths and trails impassable in winter. A short spring follows the long and harsh winter; summer has more precipitation and is followed by a mild and fine autumn. Frost is expected until Pentecost . Average annual temperatures lie between 4 and 5 °C, average precipitation

2508-567: The A-Q-P half of the diagram. True granite (according to modern petrologic convention) contains between 20% and 60% quartz by volume, with 35% to 90% of the total feldspar consisting of alkali feldspar . Granitic rocks poorer in quartz are classified as syenites or monzonites , while granitic rocks dominated by plagioclase are classified as granodiorites or tonalites . Granitic rocks with over 90% alkali feldspar are classified as alkali feldspar granites . Granitic rock with more than 60% quartz, which

2584-598: The European Union safety standards (section 4.1.1.1 of the National Health and Engineering study) and radon emission levels well below the average outdoor radon concentrations in the US. Granite and related marble industries are considered one of the oldest industries in the world, existing as far back as Ancient Egypt . Major modern exporters of granite include China, India, Italy, Brazil, Canada, Germany, Sweden, Spain and

2660-515: The Großer and Kleiner Haberstein, the Burgsteinfelsen, Mühlstein, Püttnersfel and Jakobifels) are protected natural monuments . The view of the twin peaks of Kleine and Große Kösseine (Little and Great Kösseine), visible from almost all sides, is quite striking. The Kösseine was first mentioned in the records on 7 March 1283, when large parts of the Kösseine ( Choezsin ) were transferred to Duke Louis

2736-526: The Haviland porcelain factory. At times, this important industry employed over 1,000 workers. Through modernization and streamlining the workforce was greatly reduced. Since 1937, the business has been owned by the Rosenthal Corporation. The oldest business in the city is the saw mill. It was founded in 1885 by master builder August Mayer. The ownership of the business was transferred through inheritance to

2812-497: The Kösseine as a local attraction in their advertising brochures. The mountain hut on the Kösseine has been a venue for folk musicians for a long time who, at regular intervals, play authentic folk music . Folk evenings, too, enjoy great popularity. Near the Kösseinehaus there is a large, wooden cross and a stone altar; mountaintop services on Ascension Day and other special occasions are a tradition here. Kösseine Granite , which

2888-531: The Strict, Count Palatine of Rhine and Duke of Bavaria. From 1542 (Caspar Bruschius: Des Vichtelbergs gründtliche Beschreibung ) to the present day the mountain appeared in all local geographical and historical books and was famous for its outstanding views. By the 15th century its thick woods were already a favourite hunting ground of the Bayreuth margraves , and the forests supplied wood for construction and fuel to

2964-504: The United States. The Red Pyramid of Egypt ( c.  2590 BC ), named for the light crimson hue of its exposed limestone surfaces, is the third largest of Egyptian pyramids . Pyramid of Menkaure , likely dating 2510 BC, was constructed of limestone and granite blocks. The Great Pyramid of Giza (c. 2580 BC ) contains a huge granite sarcophagus fashioned of "Red Aswan Granite". The mostly ruined Black Pyramid dating from

3040-419: The base of the chamber are the same ones that would crystallize anyway, but crustal assimilation is detectable in isotope ratios. Heat loss to the country rock means that ascent by assimilation is limited to distance similar to the height of the magma chamber. Physical weathering occurs on a large scale in the form of exfoliation joints , which are the result of granite's expanding and fracturing as pressure

3116-418: The big difference in rheology between mafic and felsic magmas makes this process problematic in nature. Granitization is an old, and largely discounted, hypothesis that granite is formed in place through extreme metasomatism . The idea behind granitization was that fluids would supposedly bring in elements such as potassium, and remove others, such as calcium, to transform a metamorphic rock into granite. This

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3192-400: The castle in Waldershof which he occupied to the monastery in Waldsassen. The castle was built in 1100 and served as the starting point for the settlement. The builder remains unknown. In 1463, Abbot Nikolaus IV of Waldsassen granted the village of Waldershof market rights. The castle and market continued to belong to the monastery of Waldsassen until secularization in 1802. The present look of

3268-416: The castle provides only an incomplete view of the original size and appearance. This huge building was covered by a pond and creek in the east as well as the south and by ringwalls on the north side. The massive, 1823 ablated watchtower at the northeast corner of the castle gave a wide view into the valley of Waldershof. The “Markt Waldershof” was pulled into the industrial age in 1907 with the construction of

3344-527: The community qualify as vacation spots, this is especially true for Shurbach, Kossain and Rodenzenreuth which are found at base of the Kossaine and Hohenhard, Poppenreuth and Helmbrechts which are situated on the north side of the Steinwald . These locations are ideal launching spots for extensive hiking and for participation in winter sports. Most parts of Waldershof belong to the nature park Steinwald . The climate

3420-540: The district of Tirschenreuth . The Fichtelgebirgsverein (publ.): The Kösseine in the Fichtelgebirge , Issue 3/1993 in the series The Fichtelgebirge . New revised, edition, 2005. Waldershof Waldershof is a town in the district of Tirschenreuth , in Bavaria , Germany . It is situated 22 km northwest of Tirschenreuth , and 3 km southwest of Marktredwitz . The 60 square kilometer City of Waldershof

3496-404: The division between S-type (produced by underplating) and I-type (produced by injection and differentiation) granites, discussed below. The composition and origin of any magma that differentiates into granite leave certain petrological evidence as to what the granite's parental rock was. The final texture and composition of a granite are generally distinctive as to its parental rock. For instance,

3572-467: The early 16th century became known as spolia . Through the process of case-hardening , granite becomes harder with age. The technology required to make tempered metal chisels was largely forgotten during the Middle Ages. As a result, Medieval stoneworkers were forced to use saws or emery to shorten ancient columns or hack them into discs. Giorgio Vasari noted in the 16th century that granite in quarries

3648-469: The family Shug. At the conclusion of World War II, many refugees found new homes in Waldershof. By 1949 existing local construction cooperatives were quickly building living quarters. In 1963, Henrich Junker, then the Bavarian Minister of State, gave Waldershof the title of “Stadt” (city). Today, the City of Waldershof is an industrial community. For hundreds of years, tradesmen and craftsmen have given

3724-579: The first magma to enter solidifies and provides a form of insulation for later magma. These mechanisms can operate in tandem. For example, diapirs may continue to rise through the brittle upper crust through stoping , where the granite cracks the roof rocks, removing blocks of the overlying crust which then sink to the bottom of the diapir while the magma rises to take their place. This can occur as piecemeal stopping (stoping of small blocks of chamber roof), as cauldron subsidence (collapse of large blocks of chamber roof), or as roof foundering (complete collapse of

3800-602: The first primitive shelter was erected and, in 1833, another one. In 1882 the Fichtelgebirge Section of the German-Austrian Alpine Club (forerunner of the Fichtelgebirge Club ) built a timber refuge hut with food for hikers. Due to the constantly rising number of visitors a permanent house was called for which was finally opened in 1903 after a long preparations and which was considerable extended in

3876-684: The grotto is a highly regarded piece of Buddhist art , and along with the temple complex to which it belongs, Seokguram was added to the UNESCO World Heritage List in 1995. Rajaraja Chola I of the Chola Dynasty in South India built the world's first temple entirely of granite in the 11th century AD in Tanjore , India . The Brihadeeswarar Temple dedicated to Lord Shiva was built in 1010. The massive Gopuram (ornate, upper section of shrine)

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3952-555: The house is out-of-bounds to private vehicles, so it can only be reached on foot. The Kösseinehaus is on the network of main hiking trails maintained by the Fichtelgebirge Club; it lies directly next to the High Way and is well used by walkers. The volunteer workers of the Fichtelgebirge Club have laid out 13 marked hiking trails of varying lengths from all directions to the summit of the Kösseine. The surrounding villages include

4028-474: The lower crust , rather than by decompression of mantle rock, as is the case with basaltic magmas. It has also been suggested that some granites found at convergent boundaries between tectonic plates , where oceanic crust subducts below continental crust, were formed from sediments subducted with the oceanic plate. The melted sediments would have produced magma intermediate in its silica content, which became further enriched in silica as it rose through

4104-697: The lower continental crust at high thermal gradients. This leads to significant extraction of hydrous felsic melts from granulite-facies resitites. A-type granites occur in the Koettlitz Glacier Alkaline Province in the Royal Society Range, Antarctica. The rhyolites of the Yellowstone Caldera are examples of volcanic equivalents of A-type granite. M-type granite was later proposed to cover those granites that were clearly sourced from crystallized mafic magmas, generally sourced from

4180-435: The magma is inevitable once enough magma has accumulated. However, the question of precisely how such large quantities of magma are able to shove aside country rock to make room for themselves (the room problem ) is still a matter of research. Two main mechanisms are thought to be important: Of these two mechanisms, Stokes diapirism has been favoured for many years in the absence of a reasonable alternative. The basic idea

4256-426: The magma. Other processes must produce these great volumes of felsic magma. One such process is injection of basaltic magma into the lower crust, followed by differentiation, which leaves any cumulates in the mantle. Another is heating of the lower crust by underplating basaltic magma, which produces felsic magma directly from crustal rock. The two processes produce different kinds of granites, which may be reflected in

4332-408: The magmatic parent of granitic rock. The residue of the source rock becomes a granulite . The partial melting of solid rocks requires high temperatures and the addition of water or other volatiles which lower the solidus temperature (temperature at which partial melting commences) of these rocks. It was long debated whether crustal thickening in orogens (mountain belts along convergent boundaries )

4408-405: The mantle. Although the fractional crystallisation of basaltic melts can yield small amounts of granites, which are sometimes found in island arcs, such granites must occur together with large amounts of basaltic rocks. H-type granites were suggested for hybrid granites, which were hypothesized to form by mixing between mafic and felsic from different sources, such as M-type and S-type. However,

4484-400: The mountain has long been a popular destination. Its fame rose considerably as a result of the visit of the nobility from 13 June 1805 to 5 July 1805 and who stayed in (Bad) Alexandersbad . On 17 June 1805 Frederick William III of Prussia and his wife Louise as well as a large entourage rode out to the Kösseine. Many newspapers reported the event and spread the mountain's renown. In 1805

4560-424: The nineties Waldershof decided once more to open up new ground for more private housing quarters. The city extended its living quarters for 3 times since. In 2014 the city council approved the demolishment of the old porcelain factory which followed a year later. This old manufacturing facility dominated the skyline of Waldershof for more than a century. Meanwhile, bicycle manufacture CUBE extended its headquarters in

4636-441: The overlying crust. Early fractional crystallisation serves to reduce a melt in magnesium and chromium, and enrich the melt in iron, sodium, potassium, aluminum, and silicon. Further fractionation reduces the content of iron, calcium, and titanium. This is reflected in the high content of alkali feldspar and quartz in granite. The presence of granitic rock in island arcs shows that fractional crystallization alone can convert

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4712-506: The people work and bread. Private housing construction also flourished. As the population grew, manufacturing companies related to sheet metal products, clothing, tools and vehicle engineering followed. Since the completion of the municipality reform, the community of Waldershof extends from the Koesseine to the southern edge of the Steinwald. A new City Hall was built in 1983. Beginning in

4788-702: The reign of Amenemhat III once had a polished granite pyramidion or capstone, which is now on display in the main hall of the Egyptian Museum in Cairo (see Dahshur ). Other uses in Ancient Egypt include columns , door lintels , sills , jambs , and wall and floor veneer. How the Egyptians worked the solid granite is still a matter of debate. Tool marks described by the Egyptologist Anna Serotta indicate

4864-551: The risk factors in granite country and design rules relating, in particular, to preventing accumulation of radon gas in enclosed basements and dwellings. A study of granite countertops was done (initiated and paid for by the Marble Institute of America) in November 2008 by National Health and Engineering Inc. of USA. In this test, all of the 39 full-size granite slabs that were measured for the study showed radiation levels well below

4940-418: The rock's high quartz content and dearth of available bases, with the base-poor status predisposing the soil to acidification and podzolization in cool humid climates as the weather-resistant quartz yields much sand. Feldspars also weather slowly in cool climes, allowing sand to dominate the fine-earth fraction. In warm humid regions, the weathering of feldspar as described above is accelerated so as to allow

5016-414: The rocks often bear a close resemblance. Under these conditions, granitic melts can be produced in place through the partial melting of metamorphic rocks by extracting melt-mobile elements such as potassium and silicon into the melts but leaving others such as calcium and iron in granulite residues. This may be the origin of migmatites . A migmatite consists of dark, refractory rock (the melanosome ) that

5092-489: The roof of a shallow magma chamber accompanied by a caldera eruption.) There is evidence for cauldron subsidence at the Mt. Ascutney intrusion in eastern Vermont. Evidence for piecemeal stoping is found in intrusions that are rimmed with igneous breccia containing fragments of country rock. Assimilation is another mechanism of ascent, where the granite melts its way up into the crust and removes overlying material in this way. This

5168-435: The surface than magmas of I-type granites, which are thus more common as volcanic rock (rhyolite). They are also orogenic but range from metaluminous to strongly peraluminous. Although both I- and S-type granites are orogenic, I-type granites are more common close to the convergent boundary than S-type. This is attributed to thicker crust further from the boundary, which results in more crustal melting. A-type granites show

5244-546: The surrounding villages. Granite quarrying began in the same century. In 1785 and 1820 Johann Wolfgang von Goethe came to the Fichtel Mountains. He wrote scientific treatises about granite weathering and made sketches of the various rock formations in the Kösseine area. Because of its clear, far-reaching views in all directions of the compass (to the Bavarian Forest , Rhön , Thuringian Forest and Ore Mountains )

5320-440: The texture is known as porphyritic . A granitic rock with a porphyritic texture is known as a granite porphyry . Granitoid is a general, descriptive field term for lighter-colored, coarse-grained igneous rocks. Petrographic examination is required for identification of specific types of granitoids. Granites can be predominantly white, pink, or gray in color, depending on their mineralogy . The alkali feldspar in granites

5396-475: The town of Waldershof, where it also decided to build its logistic center. It is located near the former porcelain facility. Waldershof is located on the train line Nuremberg-Eger and is only 3 kilometers away from the Marktredwitz train station. Through the local network of roads, Waldershof is connected to interstate highway A 93, state roads 2170, 2177 and county road TIR 17. Marktredwitz and Waldershof share

5472-502: The uranium washes into the sediments from the granite uplands and associated, often highly radioactive pegmatites. Cellars and basements built into soils over granite can become a trap for radon gas, which is formed by the decay of uranium. Radon gas poses significant health concerns and is the number two cause of lung cancer in the US behind smoking. Thorium occurs in all granites. Conway granite has been noted for its relatively high thorium concentration of 56±6 ppm. There

5548-599: The use of flint tools on finer work with harder stones, e.g. when producing the hieroglyphic inscriptions. Patrick Hunt has postulated that the Egyptians used emery , which has greater hardness. The Seokguram Grotto in Korea is a Buddhist shrine and part of the Bulguksa temple complex. Completed in 774 AD, it is an artificial grotto constructed entirely of granite. The main Buddha of

5624-483: The years that followed. In 1924 a stone observation tower , the Kösseine Tower ( Kösseineturm ), was built to replace the wooden towers. Both house and tower belong to the Fichtelgebirge Club. The house, built of Kösseine Granite and leased, offers accommodation and food all year round. From 1998 to 2000 the Kösseinehaus was fully renovated, so that it now has all the modern facilities of an inn. The forest road to

5700-405: Was sufficient to produce granite melts by radiogenic heating , but recent work suggests that this is not a viable mechanism. In-situ granitization requires heating by the asthenospheric mantle or by underplating with mantle-derived magmas. Granite magmas have a density of 2.4 Mg/m , much less than the 2.8 Mg/m of high-grade metamorphic rock. This gives them tremendous buoyancy, so that ascent of

5776-564: Was supposed to occur across a migrating front. However, experimental work had established by the 1960s that granites were of igneous origin. The mineralogical and chemical features of granite can be explained only by crystal-liquid phase relations, showing that there must have been at least enough melting to mobilize the magma. However, at sufficiently deep crustal levels, the distinction between metamorphism and crustal melting itself becomes vague. Conditions for crystallization of liquid magma are close enough to those of high-grade metamorphism that

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