1.
Sri Lanka
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Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka, is an island country in South Asia near south-east India. Sri Lanka has maritime borders with India to the northwest and the Maldives to the southwest, Sri Lankas documented history spans 3,000 years, with evidence of pre-historic human settlements dating back to at least 125,000 years. Its geographic location and deep harbours made it of strategic importance from the time of the ancient Silk Road through to World War II. Sri Lanka was known from the beginning of British colonial rule until 1972 as Ceylon, Sri Lankas recent history has been marred by a thirty-year civil war which decisively ended when the Sri Lankan military defeated the Liberation Tigers of Tamil Eelam in 2009. A diverse and multicultural country, Sri Lanka is home to many religions, ethnic groups, in addition to the majority Sinhalese, it is home to large groups of Sri Lankan and Indian Tamils, Moors, Burghers, Malays, Kaffirs and the aboriginal Vedda. Sri Lanka has a rich Buddhist heritage, and the first known Buddhist writings of Sri Lanka, Sri Lanka is a republic and a unitary state governed by a semi-presidential system. The legislative capital, Sri Jayawardenepura Kotte, is a suburb of the capital and largest city. Along with the Maldives, Sri Lanka is one of the two countries in South Asia that are rated among high human development on the Human Development Index. In antiquity, Sri Lanka was known to travellers by a variety of names, according to the Mahavamsa, the legendary Prince Vijaya named the land Tambapanni, because his followers hands were reddened by the red soil of the area. In Hindu mythology, such as the Mahabharata, the island was referred to as Lankā, in Tamil, the island is referred to as Eelam. Ancient Greek geographers called it Taprobanā or Taprobanē from the word Tambapanni, as a British crown colony, the island was known as Ceylon, it achieved independence as the Dominion of Ceylon in 1948. The country is known in Sinhalese as Śrī Laṃkā and in Tamil as Ilaṅkai, in 1972, its formal name was changed to Free, Sovereign and Independent Republic of Sri Lanka. Later in 1978 it was changed to the Democratic Socialist Republic of Sri Lanka, as the name Ceylon still appears in the names of a number of organisations, the Sri Lankan government announced in 2011 a plan to rename all those over which it has authority. The pre-history of Sri Lanka goes back 125,000 years, the era spans the Palaeolithic, Mesolithic and early Iron Ages. Among the Paleolithic human settlements discovered in Sri Lanka, Pahiyangala and it is said that Kubera was overthrown by his demon stepbrother Ravana, the powerful emperor who built a mythical flying machine named Dandu Monara. The modern city of Wariyapola is described as Ravanas airport, early inhabitants of Sri Lanka were probably ancestors of the Vedda people, an indigenous people numbering approximately 2,500 living in modern-day Sri Lanka. According to the Mahāvamsa, a written in Pāḷi, the original inhabitants of Sri Lanka are the Yakshas and Nagas. Ancient cemeteries that were used before 600BC and other signs of advanced civilization has also discovered in Sri Lanka
2.
Stupa
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A stupa is a mound-like or hemispherical structure containing relics that is used as a place of meditation. Stupas originated as pre-Buddhist tumuli in which śramaṇas were buried in a position called chaitya. After the parinirvana of the Buddha, his remains were cremated, the earliest archaeological evidence for the presence of Buddhist stupas dates to the late 4th century BCE in India. Buddhist scriptures claim that stupas were built at least a century earlier, however, some later stupas, such as at Sarnath and Sanchi, seem to be embellishments of earlier mounds. The earliest evidence of monastic stupas dates back to the 2nd century BCE and these are stupas that were built within Buddhist monastic complexes and they replicate in stone older stupas made of baked bricks and timber. Sanchi, Sarnath, Amaravati and Bharhut are examples of stupas that were shaped in stone imitating previously existing wooden parts, the stupa was elaborated as Buddhism spread to other Asian countries, becoming, for example, the chörten of Tibet and the pagoda in East Asia. The pagoda has varied forms that also include bell-shaped and pyramidal styles, in the Western context, there is no clear distinction between a stupa and a pagoda. Stupas were built in Sri Lanka soon after Devanampiya Tissa of Anuradhapura converted to Buddhism, the first stupa to be built was the Thuparamaya. Later, many more were built over the years, some like the Jetavanaramaya in Anuradhapura being one of the tallest ancient structures in the world, the earliest archaeological evidence for the presence of Buddhist stupas dates to the late 4th century BCE. In India, Sanchi, Sarnath, Amaravati and Bharhut are among the oldest known stupas, the tallest is the Phra Pathommachedi in Nakhon Pathom Province, Thailand, at a height of 127 metres. The Swat Valley hosts a well-preserved stupa at Shingardar near Ghalegay, another stupa is located near Barikot, in Sri Lanka, the ancient city of Anuradhapura includes some of the tallest, most ancient and best preserved stupas in the world, such as Ruwanwelisaya. The most elaborate stupa is the 8th century Borobudur monument in Java, the upper rounded terrace with rows of bell-shaped stupas contained Buddha images symbolizing Arūpajhāna, the sphere of formlessness. The main stupa itself is empty, symbolizing complete perfection of enlightenment, borobudurs unique and significant architecture has been acknowledged by UNESCO as the largest buddhist monument in the world. It is also the world’s largest Buddhist temple, as well as one of the greatest Buddhist monuments in the world. Object stupa, in which the items interred are objects belonged to the Buddha or his disciples, such as a bowl or robe. Commemorative stupa, built to commemorate events in the lives of Buddha or his disciples, symbolic stupa, to symbolise aspects of Buddhist theology, for example, Borobudur is considered to be the symbol of the Three Worlds and the spiritual stages in a Mahayana bodhisattvas character. Votive stupa, constructed to commemorate visits or to gain spiritual benefits, the shape of the stupa represents the Buddha, crowned and sitting in meditation posture on a lion throne. His crown is the top of the spire, his head is the square at the base, his body is the vase shape, his legs are the four steps of the lower terrace
3.
Jetavana
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Jetavana was one of the most famous of the Buddhist monasteries or viharas in India. It was the second vihara donated to Gautama Buddha after the Veluvana in Rajgir, Jetavana is located just outside the old city of Savatthi. There was also an important vihara named Jetavana in Sri Lanka, Jetavana was the place where the Buddha gave the majority of his teachings and discourses, having passed at Jetavana nineteen out of 45 vassas, more than in any other monastery. When the Buddha accepted Anāthapindikas invitation to visit Sāvatthi the latter, seeking a place for the Buddhas residence. When he asked to be allowed to buy it, Jetas reply was, Anāthapindika had gold brought down in carts and covered Jetavana with pieces laid side by side. The money brought in the first journey was found insufficient to cover one small spot near the gateway, so Anāthapindika sent his servants back for more, but Jeta, inspired by Anāthapindikas earnestness, asked to be allowed to give this spot. Anāthapindika agreed and Jeta erected there a gateway, with a room over it and it is said that Anāthapindika paid eighteen crores for the purchase of the site, all of which Jeta spent in the construction of the gateway gifted by him. Jeta gave, besides, many trees for timber. Anāthapindika himself spent fifty-four crores in connection with the purchase of the park, the ceremony of dedication was one of great splendour. Anāthapindika was attended by five hundred bankers, the festivities in connection with the dedication lasted for nine months. The vihāra is almost always referred to as Jetavane Anāthapindikassa ārāma, the vihāra is sometimes referred to as Jetārāma. Some of the buildings attached to the Jetavana are mentioned in the books by special names, viz. Mahāgandhakuti, Kaverimandalamāla, Kosambakuti. Other buildings are also mentioned - e. g. the Ambalakotthaka-āsanasālā, according to Tibetan sources the vihāra was built according to a plan sent by the devas of Tusita and contained sixty large halls and sixty small. The Dulva also gives details of the scheme of the vihāra. All these were built by Anāthapindika, there was another large building erected by Pasenadi, over the gateway lived a guardian deity to prevent all evildoers from entering. Just outside the monastery was a rājayatana-tree, the residence of the god Samiddhisumana, in the grounds there seems to have been a large pond which came to be called the Jetavanapokkharanī. The grounds themselves were covered with trees, giving the appearance of a wooded grove. On the outskirts of the monastery was a mango-grove, in front of the gateway was the Bodhi-tree planted by Anāthapindika, which came later to be called the Anandabodhi
4.
Gautama Buddha
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Gautama Buddha, also known as Siddhārtha Gautama, Shakyamuni Buddha, or simply the Buddha, after the title of Buddha, was an ascetic and sage, on whose teachings Buddhism was founded. He is believed to have lived and taught mostly in the part of ancient India sometime between the sixth and fourth centuries BCE. Gautama taught a Middle Way between sensual indulgence and the severe asceticism found in the śramaṇa movement common in his region and he later taught throughout other regions of eastern India such as Magadha and Kosala. Gautama is the figure in Buddhism. He is recognized by Buddhists as a teacher who attained full Buddhahood. Accounts of his life, discourses, and monastic rules are believed by Buddhists to have been summarized after his death, various collections of teachings attributed to him were passed down by oral tradition and first committed to writing about 400 years later. Scholars are hesitant to make unqualified claims about the facts of the Buddhas life. Apart from the Vedic Brahmins, the Buddhas lifetime coincided with the flourishing of influential schools of thought like Ājīvika, Cārvāka, Jainism. Brahmajala Sutta records sixty-two such schools of thought, thus, Buddha was just one of the many śramaṇa philosophers of that time. The times of Gautamas birth and death are uncertain, most historians in the early 20th century dated his lifetime as circa 563 BCE to 483 BCE. These alternative chronologies, however, have not yet accepted by all historians. It was either a republic, or an oligarchy, and his father was an elected chieftain. He obtained his enlightenment in Bodh Gaya, gave his first sermon in Sarnath, no written records about Gautama were found from his lifetime or some centuries thereafter. One Edict of Asoka, who reigned from circa 269 BCE to 232 BCE, another one of his edicts mentions the titles of several Dhamma texts, establishing the existence of a written Buddhist tradition at least by the time of the Maurya era. These texts may be the precursor of the Pāli Canon and they are written in the Gāndhārī language using the Kharosthi script on twenty-seven birch bark manuscripts and date from the first century BCE to the third century CE. The sources for the life of Siddhārtha Gautama are a variety of different and these include the Buddhacarita, Lalitavistara Sūtra, Mahāvastu, and the Nidānakathā. Of these, the Buddhacarita is the earliest full biography, a poem written by the poet Aśvaghoṣa in the first century CE. The Lalitavistara Sūtra is the next oldest biography, a Mahāyāna/Sarvāstivāda biography dating to the 3rd century CE, the Mahāvastu from the Mahāsāṃghika Lokottaravāda tradition is another major biography, composed incrementally until perhaps the 4th century CE
5.
Mahayana
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Mahayana is one of two main existing branches of Buddhism and a term for classification of Buddhist philosophies and practice. The Buddhist tradition of Vajrayana is sometimes classified as a part of Mahayana Buddhism, a bodhisattva who has accomplished this goal is called a samyaksaṃbuddha, or fully enlightened Buddha. A samyaksaṃbuddha can establish the Dharma and lead disciples to enlightenment, Mahayana Buddhists teach that enlightenment can be attained in a single lifetime, and this can be accomplished even by a layperson. The Mahāyāna tradition is the largest major tradition of Buddhism existing today, with 53. 2% of practitioners, major traditions of Mahāyāna Buddhism today include Chan Buddhism, Korean Seon, Japanese Zen, Pure Land Buddhism, and Nichiren Buddhism. It may also include the Vajrayana traditions of Tiantai, Tendai, Shingon Buddhism, and Tibetan Buddhism, according to Jan Nattier, the term Mahāyāna was originally an honorary synonym for Bodhisattvayāna — the vehicle of a bodhisattva seeking buddhahood for the benefit of all sentient beings. The term Mahāyāna was therefore formed independently at a date as a synonym for the path. The earliest Mahāyāna texts often use the term Mahāyāna as a synonym for Bodhisattvayāna, the presumed dichotomy between Mahāyāna and Hīnayāna can be deceptive, as the two terms were not actually formed in relation to one another in the same era. Among the earliest and most important references to the term Mahāyāna are those that occur in the Lotus Sūtra dating between the 1st century BCE and the 1st century CE. Seishi Karashima has suggested that the term first used in an earlier Gandhāri Prakrit version of the Lotus Sūtra was not the term mahāyāna, the origins of Mahāyāna are still not completely understood. The earliest Western views of Mahāyāna assumed that it existed as a school in competition with the so-called Hīnayāna schools. The earliest textual evidence of Mahāyāna comes from sūtras originating around the beginning of the common era. There is also no evidence that Mahāyāna ever referred to a formal school or sect of Buddhism, but rather that it existed as a certain set of ideals. Membership in these nikāyas, or monastic sects, continues today with the Dharmaguptaka nikāya in East Asia, therefore, Mahāyāna was never a separate rival sect of the early schools. Paul Harrison clarifies that while monastic Mahāyānists belonged to a nikāya, from Chinese monks visiting India, we now know that both Mahāyāna and non-Mahāyāna monks in India often lived in the same monasteries side by side. Those who venerate the bodhisattvas and read the Mahayana sūtras are called the Mahāyānists, much of the early extant evidence for the origins of Mahāyāna comes from early Chinese translations of Mahāyāna texts. These Mahāyāna teachings were first propagated into China by Lokakṣema, the first translator of Mahāyāna sūtras into Chinese during the 2nd century CE. Guang Xing states, Several scholars have suggested that the Prajñāpāramitā probably developed among the Mahāsāṃghikas in southern India, in the Āndhra country, warder believes that the Mahāyāna originated in the south of India and almost certainly in the Āndhra country. They note that the ancient Buddhist sites in the lower Kṛṣṇa Valley, including Amaravati, Nāgārjunakoṇḍā and Jaggayyapeṭa can be traced to at least the third century BCE, akira Hirakawa notes the evidence suggests that many Early Mahayana scriptures originated in South India
6.
Brick
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A brick is building material used to make walls, pavements and other elements in masonry construction. Traditionally, the term referred to a unit composed of clay. A brick can be composed of clay-bearing soil, sand, and lime, Bricks are produced in numerous classes, types, materials, and sizes which vary with region and time period, and are produced in bulk quantities. Two basic categories of bricks are fired and non-fired bricks, block is a similar term referring to a rectangular building unit composed of similar materials, but is usually larger than a brick. Lightweight bricks are made from expanded clay aggregate, fired bricks are one of the longest-lasting and strongest building materials, sometimes referred to as artificial stone, and have been used since circa 5000 BC. Air-dried bricks, also known as mudbricks, have an older than fired bricks. Bricks are laid in courses and numerous patterns known as bonds, collectively known as brickwork, the earliest bricks were dried brick, meaning that they were formed from clay-bearing earth or mud and dried until they were strong enough for use. The oldest discovered bricks, originally made from shaped mud and dating before 7500 BC, were found at Tell Aswad, in the upper Tigris region, ceramic, or fired brick was used as early as 3000 BC in early Indus Valley cities. In pre-modern China, bricks were being used from the 2nd millennium BCE at a site near Xian, the carpenters manual Yingzao Fashi, published in 1103 at the time of the Song dynasty described the brick making process and glazing techniques then in use. He also had to know when to quench the kiln with water so as to produce the surface glaze, Early civilisations around the Mediterranean adopted the use of fired bricks, including the Ancient Greeks and Romans. The Roman legions operated mobile kilns, and built large brick structures throughout the Roman Empire, during the Early Middle Ages the use of bricks in construction became popular in Northern Europe, after being introduced there from Northern-Western Italy. An independent style of architecture, known as brick Gothic flourished in places that lacked indigenous sources of rocks. Examples of this style can be found in modern-day Denmark, Germany, Poland. A clear distinction between the two styles developed at the transition to Baroque architecture. In Lübeck, for example, Brick Renaissance is clearly recognisable in buildings equipped with terracotta reliefs by the artist Statius von Düren, production of bricks increased massively with the onset of the Industrial Revolution and the rise in factory building in England. For reasons of speed and economy, bricks were increasingly preferred as building material to stone and it was at this time in London, that bright red brick was chosen for construction to make the buildings more visible in the heavy fog and to help prevent traffic accidents. The transition from the method of production known as hand-moulding to a mechanised form of mass-production slowly took place during the first half of the nineteenth century. His mechanical apparatus soon achieved widespread attention after it was adopted for use by the South Eastern Railway Company for brick-making at their factory near Folkestone, the Bradley & Craven Ltd ‘Stiff-Plastic Brickmaking Machine’ was patented in 1853, apparently predating Clayton
7.
Alms
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Alms or almsgiving involves giving to others as an act of virtue, either materially or in the sense of providing capabilities for free. It exists in a number of religions and regions, the word, in the modern English language, comes from the Old English ælmesse, ælmes, from Late Latin eleemosyna, from Greek ἐλεημοσύνη eleēmosynē, from ἐλεήμων, eleēmōn, from ἔλεος, eleos. In Judaism, tzedakah - a Hebrew term literally meaning righteousness but commonly used to signify charity - refers to the obligation to do what is right. Tzedakah, along with prayer and repentance, is regarded as ameliorating the consequences of bad acts, in Judaism, Tzedakah is seen as one of the greatest deeds that man can do. For that reason, while Zakat plays a larger role within Islamic charity. Zakat is the third of the five pillars of Islam, various rules attach to the practice but, in general terms, it is obligatory to give 2. 5% of ones savings and business revenue and 5–10% of ones harvest to the poor. One of the most important principles of Islam is that all belong to God and, therefore. The literal meaning of the word Zakat is to purify, to develop, according to Shariah it is an act of worship. Our possessions are purified by setting aside a proportion for those in need and this cutting back, like the pruning of plants, balances and encourages new growth. Zakat is the amount of money that every adult, mentally stable, free, the obligatory nature of Zakat is firmly established in the Quran, the Sunnah, and the consensus of the companions and the Muslim scholars. Allah states in Surah at-Taubah verses 34–35, O ye who believe, there are indeed many among the priests and anchorites, who in Falsehood devour the substance of men and hinder from the way of Allah. And there are those who bury gold and silver and spend it not in the way of Allah. - This is the which ye buried for yourselves, taste ye, then, the ye buried. Muslims of each era have agreed upon the nature of paying Zakat for gold and silver. Zakat is obligatory when a certain amount of money, called the nisab is reached or exceeded, Zakat is not obligatory if the amount owned is less than this nisab. The nisab of gold and golden currency is 20 mithqal, approximately 85 grams of pure gold, one mithqal is approximately 4.25 grams. The nisab of silver and silver currency is 200 dirhams, which is approximately 595 grams of pure silver. The nisab of other kinds of money and currency is to be scaled to that of gold, Zakat is obligatory after the money has been in the control of its owner for the span of one lunar year. Then the owner needs to pay 2. 5% of the money as Zakat
8.
Elephant
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Elephants are large mammals of the family Elephantidae and the order Proboscidea. Three species are recognised, the African bush elephant, the African forest elephant, Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia. Elephantidae is the surviving family of the order Proboscidea, other, now extinct, members of the order include deinotheres, gomphotheres, mammoths. Male African elephants are the largest extant terrestrial animals and can reach a height of 4 m, all elephants have several distinctive features, the most notable of which is a long trunk or proboscis, used for many purposes, particularly breathing, lifting water, and grasping objects. Their incisors grow into tusks, which can serve as weapons and as tools for moving objects, Elephants large ear flaps help to control their body temperature. Their pillar-like legs can carry their great weight, African elephants have larger ears and concave backs while Asian elephants have smaller ears and convex or level backs. Elephants are herbivorous and can be found in different habitats including savannahs, forests, deserts and they prefer to stay near water. They are considered to be keystone species due to their impact on their environments, other animals tend to keep their distance from elephants while predators, such as lions, tigers, hyenas, and wild dogs, usually target only young elephants. Females tend to live in groups, which can consist of one female with her calves or several related females with offspring. The groups are led by a known as the matriarch. Elephants have a society in which multiple family groups come together to socialise. Males leave their family groups when they reach puberty and may live alone or with other males, calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in the wild and they communicate by touch, sight, smell, and sound, elephants use infrasound, and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans and they appear to have self-awareness and show empathy for dying or dead individuals of their kind. African elephants are listed as vulnerable by the International Union for Conservation of Nature while the Asian elephant is classed as endangered, one of the biggest threats to elephant populations is the ivory trade, as the animals are poached for their ivory tusks. Other threats to elephants include habitat destruction and conflicts with local people. Elephants are used as working animals in Asia, in the past, they were used in war, today, they are often controversially put on display in zoos, or exploited for entertainment in circuses. Elephants are highly recognisable and have featured in art, folklore, religion, literature
9.
Sand
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Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. It is defined by size, being finer than gravel and coarser than silt, Sand can also refer to a textural class of soil or soil type, i. e. a soil containing more than 85% sand-sized particles by mass. The second most common type of sand is calcium carbonate, for example aragonite, for example, it is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years like the Caribbean. Sand is a non renewable resource over human timescales, and sand suitable for making concrete is in high demand, in terms of particle size as used by geologists, sand particles range in diameter from 0.0625 mm to 2 mm. An individual particle in this size is termed a sand grain. Sand grains are between gravel and silt, a 1953 engineering standard published by the American Association of State Highway and Transportation Officials set the minimum sand size at 0.074 mm. A1938 specification of the United States Department of Agriculture was 0.05 mm. Sand feels gritty when rubbed between the fingers. ISO14688 grades sands as fine, medium and coarse with ranges 0.063 mm to 0.2 mm to 0.63 mm to 2.0 mm. In the United States, sand is commonly divided into five sub-categories based on size, very fine sand, fine sand, medium sand, coarse sand, and very coarse sand. These sizes are based on the Krumbein phi scale, where size in Φ = -log2D, on this scale, for sand the value of Φ varies from −1 to +4, with the divisions between sub-categories at whole numbers. The composition of sand is highly variable, depending on the local rock sources. The gypsum sand dunes of the White Sands National Monument in New Mexico are famous for their bright, arkose is a sand or sandstone with considerable feldspar content, derived from weathering and erosion of a granitic rock outcrop. Some sands contain magnetite, chlorite, glauconite or gypsum, Sands rich in magnetite are dark to black in color, as are sands derived from volcanic basalts and obsidian. Chlorite-glauconite bearing sands are typically green in color, as are sands derived from basaltic with a high olivine content, many sands, especially those found extensively in Southern Europe, have iron impurities within the quartz crystals of the sand, giving a deep yellow color. Sand deposits in some areas contain garnets and other resistant minerals, the study of individual grains can reveal much historical information as to the origin and kind of transport of the grain. Quartz sand that is weathered from granite or gneiss quartz crystals will be angular. It is called grus in geology or sharp sand in the trade where it is preferred for concrete. Sand that is transported long distances by water or wind will be rounded, people who collect sand as a hobby are known as arenophiles
10.
Clay
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Clay is a fine-grained natural rock or soil material that combines one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure. Clays are plastic due to water content and become hard, brittle. Depending on the content in which it is found, clay can appear in various colours from white to dull grey or brown to deep orange-red. Although many naturally occurring deposits include both silts and clay, clays are distinguished from other fine-grained soils by differences in size, silts, which are fine-grained soils that do not include clay minerals, tend to have larger particle sizes than clays. There is, however, some overlap in size and other physical properties. The distinction between silt and clay varies by discipline, geologists and soil scientists usually consider the separation to occur at a particle size of 2 µm, sedimentologists often use 4–5 μm, and colloid chemists use 1 μm. Geotechnical engineers distinguish between silts and clays based on the plasticity properties of the soil, as measured by the soils Atterberg limits, ISO14688 grades clay particles as being smaller than 2 μm and silt particles as being larger. These solvents, usually acidic, migrate through the rock after leaching through upper weathered layers. In addition to the process, some clay minerals are formed through hydrothermal activity. There are two types of deposits, primary and secondary. Primary clays form as residual deposits in soil and remain at the site of formation, secondary clays are clays that have been transported from their original location by water erosion and deposited in a new sedimentary deposit. Clay deposits are associated with very low energy depositional environments such as large lakes. Depending on the source, there are three or four main groups of clays, kaolinite, montmorillonite-smectite, illite, and chlorite. Chlorites are not always considered to be a clay, sometimes being classified as a group within the phyllosilicates. There are approximately 30 different types of clays in these categories. Varve is clay with visible annual layers, which are formed by deposition of those layers and are marked by differences in erosion. This type of deposit is common in glacial lakes
11.
Seashell
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A seashell or sea shell, also known simply as a shell, is a hard, protective outer layer created by an animal that lives in the sea. The shell is part of the body of the animal, empty seashells are often found washed up on beaches by beachcombers. The shells are empty because the animal has died and the parts have been eaten by another animal or have rotted out. The term seashell usually refers to the exoskeleton of an invertebrate, most shells that are found on beaches are the shells of marine mollusks, partly because many of these shells endure better than other seashells. Apart from mollusk shells, other shells that can be found on beaches are those of barnacles, horseshoe crabs, marine annelid worms in the family Serpulidae create shells which are tubes made of calcium carbonate that are cemented onto other surfaces. The shells of sea urchins are called tests, and the shells of crabs. While most seashells are external, some cephalopods have internal shells, Seashells have been used by humans for many different purposes throughout history and pre-history. However, seashells are not the kind of shells, in various habitats, there are shells from freshwater animals such as freshwater mussels and freshwater snails. When the word refers only to the shells of marine mollusks. The study of the entire molluscan animal is known as malacology, Seashells are commonly found in beach drift, which is natural detritus deposited along strandlines on beaches by the waves and the tides. Shells are very often washed up onto an empty and clean. Empty seashells are often picked up by beachcombers, however, the majority of seashells which are offered for sale commercially have been collected alive and then killed and cleaned, specifically for the commercial trade. This type of large-scale exploitation can sometimes have a negative impact on local ecosystems. The word seashell is often used to only the shell of a marine mollusk. These shells are often the most commonly encountered, both in the wild, and for sale as decorative objects. Marine species of gastropods and bivalves are more numerous land and freshwater species. The shells of species also often have more sculpture and more color. Although there are a number of species of shelled mollusks that are large, there are vast numbers of extremely small species too
