1.
Egyptian Museum
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The Museum of Egyptian Antiquities, known commonly as the Egyptian Museum or Museum of Cairo, in Cairo, Egypt, is home to an extensive collection of ancient Egyptian antiquities. It has 120,000 items, with an amount on display. The edifice is one of the largest museums in the region, as of February 2017, the museum is open to the public. The Egyptian Museum of Antiquities contains many important pieces of ancient Egyptian history and it houses the world’s largest collection of Pharaonic antiquities. The Egyptian government established the museum, built in 1835 near the Ezbekeyah Garden, in 1855 Archduke Maximilian of Austria was given all of the artifacts by the Egyptian government, these are now in the Kunsthistorisches Museum, Vienna. A new museum was established at Boulaq in 1858 in a former warehouse, the building lay on the bank of the Nile River, and in 1878 it suffered significant damage in a flood of the Nile River. In 1891, the collections were moved to a royal palace. They remained there until 1902 when they were moved, for the last time, during the Egyptian Revolution of 2011, the museum was broken into, and two mummies were destroyed. Several artifacts were shown to have been damaged. Since then 25 objects have been found and those that were restored were put on display in September 2013 in an exhibition entitled Damaged and Restored. There are two floors in the museum, the ground floor and the first floor. On the ground there is an extensive collection of papyrus. The numerous pieces of papyrus are generally small fragments, due to their decay over the past two millennia, several languages are found on these pieces, including Greek, Latin, Arabic, and ancient Egyptian. The coins found on floor are made of many different metals, including gold, silver. The coins are not only Egyptian, but also Greek, Roman and this has helped historians research the history of Ancient Egyptian trade. Also on the floor are artifacts from the New Kingdom. These artifacts are generally larger than items created in earlier centuries, two special rooms contain a number of mummies of kings and other royal family members of the New Kingdom. In the garden adjacent to the building of the museum a memorial to famous egyptologists of the world is located, the Murder of Tutankhamen, A True Story
2.
Cairo
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Cairo is the capital and largest city of Egypt. Cairo has long been a center of the political and cultural life. Cairo has the oldest and largest film and music industries in the Arab world, as well as the worlds second-oldest institution of higher learning, Al-Azhar University. Many international media, businesses, and organizations have regional headquarters in the city, with a population of 6.76 million spread over 453 square kilometers, Cairo is by far the largest city in Egypt. An additional 9.5 million inhabitants live in proximity to the city. Cairo, like many other mega-cities, suffers from high levels of pollution, Cairos metro, one of only two in Africa, ranks among the fifteen busiest in the world, with over 1 billion annual passenger rides. The economy of Cairo was ranked first in the Middle East in 2005, Egyptians often refer to Cairo as Maṣr, the Egyptian Arabic name for Egypt itself, emphasizing the citys importance for the country. In Coptic the city is known as Kahire, meaning Place of the Sun, possibly referring to the ancient city of Heliopolis, the location of the ancient city is the suburb of Ain Shams. The ancient Egyptian name for the area is thought to be Khere-Ohe, The Place of Combat, sometimes the city is informally referred to as Kayro. The area around present-day Cairo, especially Memphis, had long been a point of Ancient Egypt due to its strategic location just upstream from the Nile Delta. However, the origins of the city are generally traced back to a series of settlements in the first millennium. Around the turn of the 4th century, as Memphis was continuing to decline in importance and this fortress, known as Babylon, remained the nucleus of the Roman, and, later, the Byzantine, city and is the oldest structure in the city today. It is also situated at the nucleus of the Coptic Orthodox community, many of Cairos oldest Coptic churches, including the Hanging Church, are located along the fortress walls in a section of the city known as Coptic Cairo. Following the Muslim conquest in 640 AD the conqueror Amr ibn As settled to the north of the Babylon in an area became known as al-Fustat. Originally a tented camp Fustat became a permanent settlement and the first capital of Islamic Egypt, in 750, following the overthrow of the Ummayad caliphate by the Abbasids, the new rulers created their own settlement to the northeast of Fustat which became their capital. This was known as al-Askar as it was laid out like a military camp, a rebellion in 869 by Ahmad ibn Tulun led to the abandonment of Al Askar and the building of another settlement, which became the seat of government. This was al-Qattai, to the north of Fustat and closer to the river, Al Qattai was centred around a palace and ceremonial mosque, now known as the Mosque of ibn Tulun. In 905 the Abbasids re-asserted control of the country and their returned to Fustat
3.
Egypt
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Egypt, officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia by a land bridge formed by the Sinai Peninsula. Egypt is a Mediterranean country bordered by the Gaza Strip and Israel to the northeast, the Gulf of Aqaba to the east, the Red Sea to the east and south, Sudan to the south, and Libya to the west. Across the Gulf of Aqaba lies Jordan, and across from the Sinai Peninsula lies Saudi Arabia, although Jordan and it is the worlds only contiguous Afrasian nation. Egypt has among the longest histories of any country, emerging as one of the worlds first nation states in the tenth millennium BC. Considered a cradle of civilisation, Ancient Egypt experienced some of the earliest developments of writing, agriculture, urbanisation, organised religion and central government. One of the earliest centres of Christianity, Egypt was Islamised in the century and remains a predominantly Muslim country. With over 92 million inhabitants, Egypt is the most populous country in North Africa and the Arab world, the third-most populous in Africa, and the fifteenth-most populous in the world. The great majority of its people live near the banks of the Nile River, an area of about 40,000 square kilometres, the large regions of the Sahara desert, which constitute most of Egypts territory, are sparsely inhabited. About half of Egypts residents live in areas, with most spread across the densely populated centres of greater Cairo, Alexandria. Modern Egypt is considered to be a regional and middle power, with significant cultural, political, and military influence in North Africa, the Middle East and the Muslim world. Egypts economy is one of the largest and most diversified in the Middle East, Egypt is a member of the United Nations, Non-Aligned Movement, Arab League, African Union, and Organisation of Islamic Cooperation. Miṣr is the Classical Quranic Arabic and modern name of Egypt. The name is of Semitic origin, directly cognate with other Semitic words for Egypt such as the Hebrew מִצְרַיִם, the oldest attestation of this name for Egypt is the Akkadian
4.
Egyptian hieroglyphs
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Egyptian hieroglyphs were the formal writing system used in Ancient Egypt. It combined logographic, syllabic and alphabetic elements, with a total of some 1,000 distinct characters, cursive hieroglyphs were used for religious literature on papyrus and wood. The later hieratic and demotic Egyptian scripts are derived from hieroglyphic writing, the writing system continued to be used throughout the Late Period, as well as the Persian and Ptolemaic periods. Late survivals of hieroglyphic use are found well into the Roman period, with the closing of pagan temples in the 5th century, knowledge of hieroglyphic writing was lost, and the script remained undeciphered throughout the medieval and early modern period. The decipherment of hieroglyphs would only be solved in the 1820s by Jean-François Champollion, the word hieroglyph comes from the Greek adjective ἱερογλυφικός, a compound of ἱερός and γλύφω, supposedly a calque of an Egyptian phrase mdw·w-nṯr gods words. The glyphs themselves were called τὰ ἱερογλυφικὰ γράμματα the sacred engraved letters, the word hieroglyph has become a noun in English, standing for an individual hieroglyphic character. As used in the sentence, the word hieroglyphic is an adjective. Hieroglyphs emerged from the artistic traditions of Egypt. For example, symbols on Gerzean pottery from c.4000 BC have been argued to resemble hieroglyphic writing, proto-hieroglyphic symbol systems develop in the second half of the 4th millennium BC, such as the clay labels of a Predynastic ruler called Scorpion I recovered at Abydos in 1998. The first full sentence written in hieroglyphs so far discovered was found on a seal found in the tomb of Seth-Peribsen at Umm el-Qaab. There are around 800 hieroglyphs dating back to the Old Kingdom, Middle Kingdom, by the Greco-Roman period, there are more than 5,000. However, given the lack of evidence, no definitive determination has been made as to the origin of hieroglyphics in ancient Egypt. Since the 1990s, and discoveries such as the Abydos glyphs, as writing developed and became more widespread among the Egyptian people, simplified glyph forms developed, resulting in the hieratic and demotic scripts. These variants were more suited than hieroglyphs for use on papyrus. Hieroglyphic writing was not, however, eclipsed, but existed alongside the other forms, especially in monumental, the Rosetta Stone contains three parallel scripts – hieroglyphic, demotic, and Greek. Hieroglyphs continued to be used under Persian rule, and after Alexander the Greats conquest of Egypt, during the ensuing Ptolemaic and Roman periods. It appears that the quality of comments from Greek and Roman writers about hieroglyphs came about, at least in part. Some believed that hieroglyphs may have functioned as a way to distinguish true Egyptians from some of the foreign conquerors, another reason may be the refusal to tackle a foreign culture on its own terms, which characterized Greco-Roman approaches to Egyptian culture generally
5.
Narmer
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Narmer was an ancient Egyptian king of the Early Dynastic Period. Probably the successor to the Protodynastic kings Scorpion and/or Ka, some consider him the unifier of Egypt and founder of the First Dynasty, and in turn the first king of a unified Egypt. This conclusion is based on the Narmer Palette and the two seals from the necropolis of Abydos that show him as the first king of the First Dynasty. The date commonly given for the beginning of his reign is c.3100 BC, other mainstream estimates using both the historical method and Radiocarbon dating are in the range 3273–2987 BC. Although highly inter-related, the question of “who was Menes. ”, while Menes is traditionally considered the first king of Ancient Egypt, Narmer has been identified by the majority of Egyptologists as the same person as Menes. Although vigorously debated, the predominant opinion is that Narmer was Menes, the issue is confusing because “Narmer” is a Horus Name, while “Menes” is a personal name. The difficulty is aligning the contemporary archaeological evidence which lists Horus Names with the King Lists that list personal names, two documents have been put forward as proof either that Narmer was Menes or alternatively Hor-Aha was Menes. The first is the “Naqada Label” which shows a serekh of Hor-Aha next to an enclosure inside of which are symbols that have been interpreted by scholars as the name “Menes”. The second is the impression from Abydos that alternates between a serekh of Narmer and the chessboard symbol, “mn”, which is interpreted as an abbreviation of Menes. Arguments have been made with regard to each of these documents in favour of Narmer or Hor-Aha being Menes, but in neither case, are the arguments conclusive. Two necropolis sealings, found in 1985 and 1991 in Abydos, in or near the tombs of Den and Qa’a, show Narmer as the founder of the First Dynasty, followed by Hor-Aha. The Qa’a sealing lists all eight of the kings of the First Dynasty in the correct order starting with Narmer and these necropolis sealings are strong evidence that Narmer was the first king of the First Dynasty – hence is the same person as Menes. The famous Narmer Palette, discovered by James E, since its discovery, however, it has been debated whether the Narmer Palette represents an actual historic event or is purely symbolic. Of course, the Narmer Palette could represent an historical event while at the same time having a symbolic significance. In 1993, Günter Dreyer discovered in Abydos, a “year label” of Narmer depicting the event that is depicted on the Narmer Palette. This year label shows that the Narmer Palette depicts an historical event. Archaeological evidence suggests that Egypt was at least partially unified during the reigns of Ka and Iry-Hor, but there is a substantial difference in the quantity and distribution of inscriptions with the names of those earlier kings in Lower Egypt and Canaan, compared to the inscriptions of Narmer. The archaeological evidence suggest that the unification began before Narmer, but was completed by him through the conquest of a polity in the North-West Delta as depicted on the Narmer Palette
6.
Deshret
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Deshret, from ancient Egyptian, was the formal name for the Red Crown of Lower Egypt and for the desert Red Land on either side of Kemet, the fertile Nile river basin. When combined with the Hedjet of Upper Egypt, it forms the Pschent, the Red Crown in Egyptian language hieroglyphs eventually was used as the vertical letter n. The original n hieroglyph from the Predynastic Period, and the Old Kingdom was the sign depicting ripples of water, in mythology, the earth deity Geb, original ruler of Egypt, invested Horus with the rule over Lower Egypt. The Egyptian pharaohs, who saw themselves as successors of Horus, other deities wore the deshret too, or were identified with it, such as the protective serpent goddess Wadjet and the creator-goddess of Sais, Neith, who often is shown wearing the Red Crown. The Red Crown would later be combined with the White Crown of Upper Egypt to form the Double Crown, symbolizing the rule over the whole country, as concerns deshret, the Red Land which comprised the deserts and foreign lands surrounding Egypt, Seth was its lord. It was considered a region of chaos, without law and full of dangers, none of the red crowns have survived, and it is unknown how it was constructed and what materials were used. Copper, reeds, cloth, and leather have been suggested, the Red Crown frequently is mentioned in texts and depicted in reliefs and statues. An early example is the depiction of the victorious pharaoh wearing the deshret on the Narmer Palette, a label from the reign of Djer records a royal visit to the shrine of the Deshret which may have been located at Buto in the Nile delta. The ancient Egyptian Red Crown, the Deshret crown, is one of the oldest Egyptian hieroglyphs, as an iconographic element, it is used on the famous Narmer Palette of Pharaoh Narmer as the Red Crown of the Delta, the Delta being Lower Egypt. The first usage of the Red Crown was in iconography as the symbol for Lower Egypt with the Nile Delta, later it came to be used in the Egyptian language – as an alphabetic uniliteral, vertical form for letter n as a phoneme or preposition. It became functional in running hieroglyphic texts, where either the horizontal or vertical form preposition satisfied space requirements, the Red Crown is also used as a determinative, most notably in the word for deshret. It is also used in words or names of gods. One older use of the red crown hieroglyph is to make the word, Egyptian in is used at the beginning of a text and translates as, Behold. or Lo. and is an emphatic. In the 198 BC Rosetta Stone, the Red Crown as hieroglyph has the usage mostly of the form of the preposition n. Visually it is also a hieroglyph that takes up more space-, so it may have a purpose of a less compact text. The Red Crown hieroglyph is used 35 times in the Rosetta Stone and it averages once per line usage in the 36 line Decree of Memphis -. Deshret, the Red Crown of the Pharaoh Gardiners Sign List#S. Crowns, Dress, Staves, Gardiners Sign List Deshret in hieroglyphic writing Budge. An Egyptian Hieroglyphic Dictionary, E. A. Wallace Budge, c 1978, the Rosetta Stone, E. A. Wallace Budge, c 1929, Dover edition,1989
7.
Art of ancient Egypt
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Ancient Egyptian art is the painting, sculpture, architecture and other arts produced by the civilization of ancient Egypt in the lower Nile Valley from about 3000 BC to 30 AD. Ancient Egyptian art reached a level in painting and sculpture. It was famously conservative, and Egyptian styles changed remarkably little over more than three thousand years, much of the surviving art comes from tombs and monuments and thus there is an emphasis on life after death and the preservation of knowledge of the past. Ancient Egyptian art included paintings, sculpture in wood, stone and ceramics, drawings on papyrus, faience, jewelry, ivories and it displays an extraordinarily vivid representation of the ancient Egyptians socioeconomic status and belief systems. This appears as early as the Narmer Palette from Dynasty I, other conventions make statues of males darker than females ones. Egyptian art uses hierarchical proportion, where the size of figures indicates their relative importance, symbolism can be observed throughout Egyptian art and played an important role in establishing a sense of order. The pharaohs regalia, for example, represented his power to maintain order, animals were also highly symbolic figures in Egyptian art. Not all Egyptian reliefs were painted, and less prestigious works in tombs, Stone surfaces were prepared by whitewash, or if rough, a layer of coarse mud plaster, with a smoother gesso layer above, some finer limestones could take paint directly. Pigments were mostly mineral, chosen to withstand sunlight without fading. The binding medium used in painting remains unclear, egg tempera and various gums and it is clear that true fresco, painted into a thin layer of wet plaster, was not used. Instead the paint was applied to dried plaster, in what is called fresco a secco in Italian, small objects including wooden statuettes were often painted using similar techniques. Many ancient Egyptian paintings have survived in tombs, and sometimes temples, the paintings were often made with the intent of making a pleasant afterlife for the deceased. The themes included journey through the afterworld or protective deities introducing the deceased to the gods of the underworld, some tomb paintings show activities that the deceased were involved in when they were alive and wished to carry on doing for eternity. In the New Kingdom and later, the Book of the Dead was buried with the entombed person and it was considered important for an introduction to the afterlife. Egyptian paintings are painted in such a way to show a profile view, for example, the painting to the right shows the head from a profile view and the body from a frontal view. Their main colors were red, blue, green, gold, black, the monumental sculpture of ancient Egypts temples and tombs is world-famous, but refined and delicate small works exist in much greater numbers. The Egyptians used the technique of sunk relief, which is well suited to very bright sunlight. The distinctive pose of standing statues facing forward with one foot in front of the other was helpful for the balance and it was adopted very early and remained unchanged until the arrival of the Greeks
8.
United Kingdom
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The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom or Britain, is a sovereign country in western Europe. Lying off the north-western coast of the European mainland, the United Kingdom includes the island of Great Britain, Northern Ireland is the only part of the United Kingdom that shares a land border with another sovereign state—the Republic of Ireland. The Irish Sea lies between Great Britain and Ireland, with an area of 242,500 square kilometres, the United Kingdom is the 78th-largest sovereign state in the world and the 11th-largest in Europe. It is also the 21st-most populous country, with an estimated 65.1 million inhabitants, together, this makes it the fourth-most densely populated country in the European Union. The United Kingdom is a monarchy with a parliamentary system of governance. The monarch is Queen Elizabeth II, who has reigned since 6 February 1952, other major urban areas in the United Kingdom include the regions of Birmingham, Leeds, Glasgow, Liverpool and Manchester. The United Kingdom consists of four countries—England, Scotland, Wales, the last three have devolved administrations, each with varying powers, based in their capitals, Edinburgh, Cardiff and Belfast, respectively. The relationships among the countries of the UK have changed over time, Wales was annexed by the Kingdom of England under the Laws in Wales Acts 1535 and 1542. A treaty between England and Scotland resulted in 1707 in a unified Kingdom of Great Britain, which merged in 1801 with the Kingdom of Ireland to form the United Kingdom of Great Britain and Ireland. Five-sixths of Ireland seceded from the UK in 1922, leaving the present formulation of the United Kingdom of Great Britain, there are fourteen British Overseas Territories. These are the remnants of the British Empire which, at its height in the 1920s, British influence can be observed in the language, culture and legal systems of many of its former colonies. The United Kingdom is a country and has the worlds fifth-largest economy by nominal GDP. The UK is considered to have an economy and is categorised as very high in the Human Development Index. It was the worlds first industrialised country and the worlds foremost power during the 19th, the UK remains a great power with considerable economic, cultural, military, scientific and political influence internationally. It is a nuclear weapons state and its military expenditure ranks fourth or fifth in the world. The UK has been a permanent member of the United Nations Security Council since its first session in 1946 and it has been a leading member state of the EU and its predecessor, the European Economic Community, since 1973. However, on 23 June 2016, a referendum on the UKs membership of the EU resulted in a decision to leave. The Acts of Union 1800 united the Kingdom of Great Britain, Scotland, Wales and Northern Ireland have devolved self-government
9.
Archaeology
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Archaeology, or archeology, is the study of human activity through the recovery and analysis of material culture. The archaeological record consists of artifacts, architecture, biofacts or ecofacts, Archaeology can be considered both a social science and a branch of the humanities. In North America, archaeology is considered a sub-field of anthropology, archaeologists study human prehistory and history, from the development of the first stone tools at Lomekwi in East Africa 3.3 million years ago up until recent decades. Archaeology as a field is distinct from the discipline of palaeontology, Archaeology is particularly important for learning about prehistoric societies, for whom there may be no written records to study. Prehistory includes over 99% of the human past, from the Paleolithic until the advent of literacy in societies across the world, Archaeology has various goals, which range from understanding culture history to reconstructing past lifeways to documenting and explaining changes in human societies through time. The discipline involves surveying, excavation and eventually analysis of data collected to learn more about the past, in broad scope, archaeology relies on cross-disciplinary research. Archaeology developed out of antiquarianism in Europe during the 19th century, Archaeology has been used by nation-states to create particular visions of the past. Nonetheless, today, archaeologists face many problems, such as dealing with pseudoarchaeology, the looting of artifacts, a lack of public interest, the science of archaeology grew out of the older multi-disciplinary study known as antiquarianism. Antiquarians studied history with attention to ancient artifacts and manuscripts. Tentative steps towards the systematization of archaeology as a science took place during the Enlightenment era in Europe in the 17th and 18th centuries, in Europe, philosophical interest in the remains of Greco-Roman civilization and the rediscovery of classical culture began in the late Middle Age. Antiquarians, including John Leland and William Camden, conducted surveys of the English countryside, one of the first sites to undergo archaeological excavation was Stonehenge and other megalithic monuments in England. John Aubrey was a pioneer archaeologist who recorded numerous megalithic and other monuments in southern England. He was also ahead of his time in the analysis of his findings and he attempted to chart the chronological stylistic evolution of handwriting, medieval architecture, costume, and shield-shapes. Excavations were also carried out in the ancient towns of Pompeii and Herculaneum and these excavations began in 1748 in Pompeii, while in Herculaneum they began in 1738. The discovery of entire towns, complete with utensils and even human shapes, however, prior to the development of modern techniques, excavations tended to be haphazard, the importance of concepts such as stratification and context were overlooked. The father of archaeological excavation was William Cunnington and he undertook excavations in Wiltshire from around 1798, funded by Sir Richard Colt Hoare. Cunnington made meticulous recordings of neolithic and Bronze Age barrows, one of the major achievements of 19th century archaeology was the development of stratigraphy. The idea of overlapping strata tracing back to successive periods was borrowed from the new geological and paleontological work of scholars like William Smith, James Hutton, the application of stratigraphy to archaeology first took place with the excavations of prehistorical and Bronze Age sites
10.
Slate
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Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. It is the finest grained foliated metamorphic rock, foliation may not correspond to the original sedimentary layering, but instead is in planes perpendicular to the direction of metamorphic compression. The foliation in slate is called slaty cleavage and it is caused by strong compression causing fine grained clay flakes to regrow in planes perpendicular to the compression. Slate is frequently grey in color, especially when seen, en masse, Slate is not to be confused with shale, from which it may be formed, or schist. The word slate is used for certain types of object made from slate rock. It may mean a single roofing tile made of slate, or a writing slate and this was traditionally a small smooth piece of the rock, often framed in wood, used with chalk as a notepad or noticeboard, and especially for recording charges in pubs and inns. The phrases clean slate and blank slate come from this usage, before the mid-19th century, the terms slate, shale and schist were not sharply distinguished. In the context of underground mining in the United States. For example, roof slate referred to shale above a coal seam, occasionally, as in the purple slates of North Wales, ferrous reduction spheres form around iron nuclei, leaving a light green spotted texture. These spheres are sometimes deformed by a subsequent applied stress field to ovoids, Slate can be made into roofing slates, a type of roof shingle, or more specifically a type of roof tile, which are installed by a slater. Slate has two lines of breakability – cleavage and grain – which make it possible to split the stone into thin sheets, when broken, slate retains a natural appearance while remaining relatively flat and easy to stack. Slate is particularly suitable as a material as it has an extremely low water absorption index of less than 0. 4%. In fact, this natural slate, which requires only minimal processing, has the lowest embodied energy of all roofing materials, natural slate is used by building professionals as a result of its beauty and durability. Slate is incredibly durable and can last several hundred years, often little or no maintenance. Its low water makes it very resistant to frost damage and breakage due to freezing. Natural slate is also fire resistant and energy efficient, Slate roof tiles are usually fixed either with nails, or with hooks as is common with Spanish slate. In the UK, fixing is typically with double nails onto timber battens or nailed directly onto timber sarking boards, nails were traditionally of copper, although there are modern alloy and stainless steel alternatives. Both these methods, if used properly, provide a long-lasting weathertight roof with a lifespan of around 80–100 years, Slate roofs are still used today
11.
Schist
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Schist is a medium-grade metamorphic rock with medium to large, flat, sheet-like grains in a preferred orientation. It is defined by having more than 50% platy and elongated minerals, often finely interleaved with quartz and these lamellar minerals include micas, chlorite, talc, hornblende, graphite, and others. Quartz often occurs in drawn-out grains to such an extent that a form called quartz schist is produced. Schist forms at a temperature and has larger grains than phyllite. Geological foliation with medium to large grained flakes in a preferred orientation is called schistosity. The names of various schists are derived from their mineral constituents, for example, schists rich in mica are called mica schists and include biotite or muscovite. Most schists are mica schists, but graphite and chlorite schists are also common, Schists are also named for their prominent or perhaps unusual mineral constituents, as in the case of garnet schist, tourmaline schist, and glaucophane schist. The individual mineral grains in schist, drawn out into flaky scales by heat and pressure, Schist is characteristically foliated, meaning that the individual mineral grains split off easily into flakes or slabs. Most schists are derived from clays and muds that have passed through a series of processes involving the production of shales, slates and phyllites as intermediate steps. Certain schists are derived from fine-grained igneous rocks such as basalts, before the mid-18th century, the terms slate, shale and schist were not sharply differentiated by those involved with mining. In the context of underground mining, shale was frequently referred to as slate well into the 20th century. During metamorphism, rocks which were originally sedimentary, igneous or metamorphic are converted into schists, if the composition of the rocks was originally similar, they may be very difficult to distinguish from one another if the metamorphism has been great. A quartz-porphyry, for example, and a fine grained feldspathic sandstone, usually, however, it is possible to distinguish between sedimentary and igneous schists and gneisses. If, for example, the district occupied by these rocks has traces of bedding, clastic structure, or unconformability. In other cases intrusive junctions, chilled edges, contact alteration or porphyritic structure may prove that in its original condition a metamorphic gneiss was an igneous rock. Such rocks as limestones, dolomites, quartzites and aluminous shales have very definite chemical characteristics which distinguish them even when completely recrystallized, the schists are classified principally according to the minerals they consist of and on their chemical composition. For example, many metamorphic limestones, marbles, and calc-schists, with crystalline dolomites, contain silicate minerals such as mica, tremolite, diopside, scapolite, quartz and they are derived from calcareous sediments of different degrees of purity. Another group is rich in quartz, with amounts of white and black mica, garnet, feldspar, zoisite
12.
Metamorphic rock
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Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means change in form. The original rock is subjected to heat and pressure, causing profound physical and/or chemical change, the protolith may be a sedimentary, an igneous, or even an existing type of metamorphic rock. Metamorphic rocks make up a part of the Earths crust. They are classified by texture and by chemical and mineral assemblage and they may be formed simply by being deep beneath the Earths surface, subjected to high temperatures and the great pressure of the rock layers above it. They can form from tectonic processes such as continental collisions, which cause horizontal pressure and they are also formed when rock is heated up by the intrusion of hot molten rock called magma from the Earths interior. The study of rocks provides information about the temperatures and pressures that occur at great depths within the Earths crust. Some examples of rocks are gneiss, slate, marble, schist. Metamorphic minerals are those that only at the high temperatures and pressures associated with the process of metamorphism. These minerals, known as index minerals, include sillimanite, kyanite, staurolite, andalusite, and some garnet. Other minerals, such as olivines, pyroxenes, amphiboles, micas, feldspars, and quartz, may be found in metamorphic rocks and these minerals formed during the crystallization of igneous rocks. They are stable at temperatures and pressures and may remain chemically unchanged during the metamorphic process. However, all minerals are only within certain limits. The change in the size of the rock during the process of metamorphism is called recrystallization. Both high temperatures and pressures contribute to recrystallization, high temperatures allow the atoms and ions in solid crystals to migrate, thus reorganizing the crystals, while high pressures cause solution of the crystals within the rock at their point of contact. The layering within metamorphic rocks is called foliation, and it occurs when a rock is being shortened along one axis during recrystallization. This causes the platy or elongated crystals of minerals, such as mica and chlorite and this results in a banded, or foliated rock, with the bands showing the colors of the minerals that formed them. Textures are separated into foliated and non-foliated categories, foliated rock is a product of differential stress that deforms the rock in one plane, sometimes creating a plane of cleavage. For example, slate is a metamorphic rock, originating from shale
