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Metals Of Antiquity
The metals of antiquity are the seven metals which humans had identified and found use for in prehistoric times in Europe and the Middle East: gold, silver, copper, tin, lead, iron, and mercury. These seven are the metals from which the modern world was forged; until the discovery of antimony in the 9th century,George Sarton, ''Introduction to the History of Science''. "We find in his writings ..preparation of various substances (e.g., basic lead carbonatic, arsenic and antimony from their sulphides)." and arsenic in the 13th (both now classified as metalloids), these were the only known elemental metals, compared to approximately 90 known today. Characteristics Melting point The metals of antiquity generally have low melting points, with iron being the exception. * Mercury melts at −38.829 °C (-37.89 °F) (being liquid at room temperature). * Tin melts at 231 °C (449 °F) * Lead melts at 327 °C (621 °F) * Silver at 961 °C (1763&nb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amulet To Protect Against Health Problems, Germany, 1701-190 Wellcome L0058949
An amulet, also known as a good luck charm or phylactery, is an object believed to confer protection upon its possessor. The word "amulet" comes from the Latin word amuletum, which Pliny's ''Natural History'' describes as "an object that protects a person from trouble". Anything can function as an amulet; items commonly so used include statues, coins, drawings, plant parts, animal parts, and written words. Amulets which are said to derive their extraordinary properties and powers from magic or those which impart luck are typically part of folk religion or paganism, whereas amulets or sacramental, sacred objects of organized religion, formalised mainstream religion as in Christianity are believed to have no power of their own without faith in Jesus and being blessing, blessed by a clergyman, and they supposedly will also not provide any preternatural benefit to the bearer who does not have an Disposition#In religion, appropriate disposition. Talisman and amulets have interchangeabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Native Metal
A native metal is any metal that is found pure in its metallic form in nature. Metals that can be found as native deposits singly or in alloys include aluminium, antimony, arsenic, bismuth, cadmium, chromium, cobalt, indium, iron, manganese, molybdenum, nickel, niobium, rhenium, selenium, tantalum, tellurium, tin, titanium, tungsten, vanadium, and zinc, as well as the gold group (gold, copper, lead, aluminium, mercury, silver) and the platinum group (platinum, iridium, osmium, palladium, rhodium, ruthenium). Among the alloys found in native state have been brass, bronze, pewter, German silver, osmiridium, electrum, white gold, silver-mercury amalgam, and gold-mercury amalgam. Only gold, silver, copper and the platinum group occur native in large amounts. Over geological time scales, very few metals can resist natural weathering processes like oxidation, so mainly the less reactive metals such as gold and platinum are found as native metals. The others usually occur as isol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alchemy
Alchemy (from Arabic: ''al-kīmiyā''; from Ancient Greek: χυμεία, ''khumeía'') is an ancient branch of natural philosophy, a philosophical and protoscientific tradition that was historically practiced in China, India, the Muslim world, and Europe. In its Western form, alchemy is first attested in a number of pseudepigraphical texts written in Greco-Roman Egypt during the first few centuries AD.Principe, Lawrence M. The secrets of alchemy'. University of Chicago Press, 2012, pp. 9–14. Alchemists attempted to purify, mature, and perfect certain materials. Common aims were chrysopoeia, the transmutation of "base metals" (e.g., lead) into "noble metals" (particularly gold); the creation of an elixir of immortality; and the creation of panaceas able to cure any disease. The perfection of the human body and soul was thought to result from the alchemical ''magnum opus'' ("Great Work"). The concept of creating the philosophers' stone was variously connected with all of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Metallurgy In Africa
The topic of early iron-metallurgy in Africa encompasses both studies of the technology and archaeology of indigenous iron-production. Some recent studies date the inception of iron metallurgy in Africa between 3000 and 2500 BCE. Evidence exists for earlier iron metallurgy in parts of Nigeria, Cameroon, and Central Africa, possibly from as early as around 2,000 BCE. Some evidence from historical linguistics suggests that the Nok culture of Nigeria may have practiced iron smelting from as early as 1000 BCE. The nearby Djenné-Djenno culture of the Niger Valley in Mali shows evidence of iron production from 250 BCE. The Bantu expansion spread the technology to Eastern and Southern Africa during 500 BCE to 400 CE, as shown in the Urewe culture of the Lake Victoria region. Iron has a number of advantages over copper, brass, wood, and stone. The use of iron ushered in an Iron Age in Africa, with the expansion of agriculture, industry, trade, and political power. In some African c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper Metallurgy In Africa
Copper metallurgy in Africa encompasses the study of copper production across the continent and an understanding of how it influenced aspects of African archaeology. Origins Scholars previously believed that sub-Saharan Africans either did not have a period of using copper until the nineteenth century (going from the Stone Age directly into the Iron Age), or that they started smelting iron and copper at the same time (Herbert 1984). Copper smelting is thought to have been practiced in Nubia, during the early Old Kingdom c. 2686–2181 BC (Childs and Killick 1993). The principal evidence for this claim is an Egyptian outpost established in Buhen (near today's Sudanese-Egyptian border) around 2600 BC to smelt copper ores from Nubia. Alongside this, a crucible furnace dating to 2300–1900 BC for bronze casting has been found at the temple precinct at Kerma (in present-day northern Sudan), however the source of the tin remains unknown. Over the next millennium Nubians developed great ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metallurgy In Pre-Columbian America
Metallurgy in pre-Columbian America is the extraction, purification and alloying of metals and metal crafting by Indigenous peoples of the Americas prior to European contact in the late 15th century. Indigenous Americans have been using native metals from ancient times, with recent finds of gold artifacts in the Andean region dated to 2155–1936 , and North American copper finds dated to approximately 5000 . The metal would have been found in nature without need for smelting, and shaped into the desired form using hot and cold hammering without chemical alteration or alloying. To date "no one has found evidence that points to the use of melting, smelting and casting in prehistoric eastern North America." In South America the case is quite different: Indigenous South Americans had full metallurgy with smelting and various metals being purposely alloyed. Metallurgy in Mesoamerica and Western Mexico may have developed following contact with South America through E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of Metallurgy In China
Metallurgy in China has a long history, with the earliest metal objects in China dating back to around 3,000 BCE. The majority of early metal items found in China come from the North-Western Region (mainly Gansu and Qinghai, 青海). China was the earliest civilization to use the blast furnace and produce cast iron. Copper Archaeological evidence indicates that the earliest metal objects in China were made in the late fourth millennium BCE. Copper was generally the earliest metal to be used by humanity, and was used in China since at least 3000 BCE. Early metal-using communities have been found at the Qijia and Siba sites in Gansu, with similar sites in Xinjiang in the west and Shandong, Liaoning and Inner Mongolia in the east and north. The Central Plain sites associated with the Erlitou culture also contain early metalworks.Katheryn M. Linduff, Jianjun Mei (2008)''Metallurgy in Ancient Eastern Asia: How is it Studied? Where is the Field Headed?'' (PDF)The British Museum Co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of Metallurgy In The Indian Subcontinent
The history of metallurgy in the Indian subcontinent began prior to the 3rd millennium BCE and continued well into the British Raj. Metals and related concepts were mentioned in various early Vedic age texts. The Rigveda already uses the Sanskrit term Ayas(आयस) (metal). The Indian cultural and commercial contacts with the Near East and the Greco-Roman world enabled an exchange of metallurgic sciences. With the advent of the Mughals (established: April 21, 1526—ended: September 21, 1857) further improved the established tradition of metallurgy and metal working in India. During the period of British rule in India (first by the East India Company and then by the Crown), the metalworking industry in India stagnated due to various colonial policies, though efforts by industrialists led to the industry's revival during the 19th century. Overview Recent excavations in Middle Ganga Valley done by archaeologist Rakesh Tewari show iron working in India may have begun as early as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ashtadhatu
Ashtadhatu (), also called octo-alloy, is an alloy often used for casting metallic idols for Jain and Hindu temples in India. The composition is laid down in the ''Shilpa shastras'', a collection of ancient texts that describe arts, crafts, and their design rules, principles and standards. Ashtadhatu is used because it is considered extremely pure, ''sattvic'' of Sattva, in Hinduism, and does not decay, and it is also restricted to the gods Kubera, Vishnu, Krishna, Rama, Kartikeya, and goddesses, Durga and Lakshmi. Its traditional composition is gold, silver, copper, lead, zinc, tin, iron and antimony or mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc .... In genuine Ashtadhatu, all eight metals are in equal proportion (12.5% each). Sometimes an alloy idol is termed Ashtad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timeline Of Chemical Element Discoveries
The discovery of the 118 chemical elements known to exist as of 2022 is presented in chronological order. The elements are listed generally in the order in which each was first defined as the pure element, as the exact date of discovery of most elements cannot be accurately determined. There are plans to synthesize more elements, and it is not known how many elements are possible. Each element's name, atomic number, year of first report, name of the discoverer, and notes related to the discovery are listed. Periodic table of elements Ancient discoveries Modern discoveries Graphics See also * History of the periodic table * Periodic table * Extended periodic table * ''The Mystery of Matter: Search for the Elements'' (2014/2015 PBS film) * Transfermium Wars References External linksHistory of the Origin of the Chemical Elements and Their DiscoverersLast updated by Boris Pritychenko on March 30, 2004 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminium
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It has a great affinity towards oxygen, and forms a protective layer of oxide on the surface when exposed to air. Aluminium visually resembles silver, both in its color and in its great ability to reflect light. It is soft, non-magnetic and ductile. It has one stable isotope, 27Al; this isotope is very common, making aluminium the twelfth most common element in the Universe. The radioactivity of 26Al is used in radiodating. Chemically, aluminium is a post-transition metal in the boron group; as is common for the group, aluminium forms compounds primarily in the +3 oxidation state. The aluminium cation Al3+ is small and highly charged; as such, it is polarizing, and bonds aluminium forms tend towards covalency. The strong affinity tow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in sea water, aqua regia, and chlorine. Titanium was discovered in Cornwall, Great Britain, by William Gregor in 1791 and was named by Martin Heinrich Klaproth after the Titans of Greek mythology. The element occurs within a number of minerals, principally rutile and ilmenite, which are widely distributed in the Earth's crust and lithosphere; it is found in almost all living things, as well as bodies of water, rocks, and soils. The metal is extracted from its principal mineral ores by the Kroll and Hunter processes. The most common compound, titanium dioxide, is a popular photocatalyst and is used in the manufacture of white pigments. Other compounds include titanium tetrachloride (TiCl4), a component of smoke screens and catalysts; and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
