1.
United States dollar
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The United States dollar is the official currency of the United States and its insular territories per the United States Constitution. It is divided into 100 smaller cent units, the circulating paper money consists of Federal Reserve Notes that are denominated in United States dollars. The U. S. dollar was originally commodity money of silver as enacted by the Coinage Act of 1792 which determined the dollar to be 371 4/16 grain pure or 416 grain standard silver, the currency most used in international transactions, it is the worlds primary reserve currency. Several countries use it as their currency, and in many others it is the de facto currency. Besides the United States, it is used as the sole currency in two British Overseas Territories in the Caribbean, the British Virgin Islands and Turks and Caicos Islands. A few countries use the Federal Reserve Notes for paper money, while the country mints its own coins, or also accepts U. S. coins that can be used as payment in U. S. dollars. After Nixon shock of 1971, USD became fiat currency, Article I, Section 8 of the U. S. Constitution provides that the Congress has the power To coin money, laws implementing this power are currently codified at 31 U. S. C. Section 5112 prescribes the forms in which the United States dollars should be issued and these coins are both designated in Section 5112 as legal tender in payment of debts. The Sacagawea dollar is one example of the copper alloy dollar, the pure silver dollar is known as the American Silver Eagle. Section 5112 also provides for the minting and issuance of other coins and these other coins are more fully described in Coins of the United States dollar. The Constitution provides that a regular Statement and Account of the Receipts and that provision of the Constitution is made specific by Section 331 of Title 31 of the United States Code. The sums of money reported in the Statements are currently being expressed in U. S. dollars, the U. S. dollar may therefore be described as the unit of account of the United States. The word dollar is one of the words in the first paragraph of Section 9 of Article I of the Constitution, there, dollars is a reference to the Spanish milled dollar, a coin that had a monetary value of 8 Spanish units of currency, or reales. In 1792 the U. S. Congress passed a Coinage Act, Section 20 of the act provided, That the money of account of the United States shall be expressed in dollars, or units. And that all accounts in the offices and all proceedings in the courts of the United States shall be kept and had in conformity to this regulation. In other words, this act designated the United States dollar as the unit of currency of the United States, unlike the Spanish milled dollar the U. S. dollar is based upon a decimal system of values. Both one-dollar coins and notes are produced today, although the form is significantly more common
2.
Abraham Lincoln
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Abraham Lincoln was an American politician and lawyer who served as the 16th President of the United States from March 1861 until his assassination in April 1865. Lincoln led the United States through its Civil War—its bloodiest war and perhaps its greatest moral, constitutional, in doing so, he preserved the Union, abolished slavery, strengthened the federal government, and modernized the economy. Born in Hodgenville, Kentucky, Lincoln grew up on the frontier in Kentucky. Largely self-educated, he became a lawyer in Illinois, a Whig Party leader, elected to the United States House of Representatives in 1846, Lincoln promoted rapid modernization of the economy through banks, tariffs, and railroads. Reentering politics in 1854, he became a leader in building the new Republican Party, in 1860, Lincoln secured the Republican Party presidential nomination as a moderate from a swing state. Though he gained little support in the slaveholding states of the South. Subsequently, on April 12,1861, a Confederate attack on Fort Sumter inspired the North to enthusiastically rally behind the Union. Politically, Lincoln fought back by pitting his opponents against each other, by carefully planned political patronage and his Gettysburg Address became an iconic endorsement of the principles of nationalism, republicanism, equal rights, liberty, and democracy. Lincoln initially concentrated on the military and political dimensions of the war and his primary goal was to reunite the nation. He suspended habeas corpus, leading to the ex parte Merryman decision. Lincoln closely supervised the war effort, especially the selection of top generals, including his most successful general, Lincoln tried repeatedly to capture the Confederate capital at Richmond, each time a general failed, Lincoln substituted another, until finally Grant succeeded. As the war progressed, his moves toward ending slavery included the Emancipation Proclamation of 1863. On April 14,1865, five days after the surrender of Confederate commanding general Robert E. Lee, Lincoln was assassinated by John Wilkes Booth, a Confederate sympathizer. Secretary of War Edwin Stanton launched a manhunt for Booth, and 12 days later on April 26, Lincoln has been consistently ranked both by scholars and the public as among the greatest U. S. presidents. Abraham Lincoln was born February 12,1809, the child of Thomas and Nancy Hanks Lincoln, in a one-room log cabin on the Sinking Spring Farm near Hodgenville. He was a descendant of Samuel Lincoln, an Englishman who migrated from Hingham, Norfolk to its namesake of Hingham, samuels grandson and great-grandson began the familys western migration, which passed through New Jersey, Pennsylvania, and Virginia. Lincolns paternal grandfather and namesake, Captain Abraham Lincoln, moved the family from Virginia to Jefferson County, Captain Lincoln was killed in an Indian raid in 1786. His children, including eight-year-old Thomas, the presidents father
3.
Victor David Brenner
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Victor David Brenner was a Litvak-American sculptor, engraver, and medalist known primarily as the designer of the United States Lincoln Cent. Brenner was born to Jewish parents in Šiauliai, Lithuania and his name at birth was Viktoras Baranauskas, but he changed the name to Victor David Brenner, because this made it easier to obtain American citizenship. He emigrated to the United States in 1890, living mostly in the New York City area, when Brenner arrived in America, he had little more to fall back upon except the trade taught him by his father — gem and seal engraving. This technical preparation included the tools of the sculptors craft and he took night classes at Cooper Union. Brenner soon mastered English as he had mastered French, eight years later Brenner was in Paris, studying with the great French medalist, Oscar Roty at the Académie Julian. There he exhibited his work and obtained awards at the Paris Exposition of 1900 and he returned to the United States, and from that time on his career prospered. He appeared to be on his way to the fulfillment of the predictions made for his future by Rodin. Brenner died in 1924 and is buried at Mount Judah Cemetery, Ridgewood, Queens County, Brenner is probably best known for his enduring Lincoln coin design, the obverse of which is the longest-running design in United States Mint history. Brenners design had been picked by 26th U. S. President, Theodore Roosevelt, since arriving nineteen years earlier in the United States, Brenner had become one of the nations premier medalists. Bronze bas-reliefs dated 1907 and signed by Brenner have been identified, charles Eliot Norton of Harvard, whom Brenner counted among his friends, gave the sculptor an unpublished portrait of Lincoln which served Brenner as a basis for Lincolns features. The Director, however, decided to have the initials substituted for the name, following the precedent of James B. Widespread criticism of the initials prominence resulted in their removal midway through 1909, in 1918, Brenners initials returned as small letters below Lincolns shoulder, where they remain today. A1909 VDB US cent was mounted on the target on the Mars Curiosity Rover. This is a nod to the rovers geologic mission and the practice by geologists including a coin in photographs to document the size of objects. Some of Brenners most noteworthy works include, Rev. Dr Muhlenberg Medal Portrait-plaquette of Fridtjof Nansen Portrait medallion of J. Sanford Saltus Portrait medallion of C
4.
United States
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Forty-eight of the fifty states and the federal district are contiguous and located in North America between Canada and Mexico. The state of Alaska is in the northwest corner of North America, bordered by Canada to the east, the state of Hawaii is an archipelago in the mid-Pacific Ocean. The U. S. territories are scattered about the Pacific Ocean, the geography, climate and wildlife of the country are extremely diverse. At 3.8 million square miles and with over 324 million people, the United States is the worlds third- or fourth-largest country by area, third-largest by land area. It is one of the worlds most ethnically diverse and multicultural nations, paleo-Indians migrated from Asia to the North American mainland at least 15,000 years ago. European colonization began in the 16th century, the United States emerged from 13 British colonies along the East Coast. Numerous disputes between Great Britain and the following the Seven Years War led to the American Revolution. On July 4,1776, during the course of the American Revolutionary War, the war ended in 1783 with recognition of the independence of the United States by Great Britain, representing the first successful war of independence against a European power. The current constitution was adopted in 1788, after the Articles of Confederation, the first ten amendments, collectively named the Bill of Rights, were ratified in 1791 and designed to guarantee many fundamental civil liberties. During the second half of the 19th century, the American Civil War led to the end of slavery in the country. By the end of century, the United States extended into the Pacific Ocean. The Spanish–American War and World War I confirmed the status as a global military power. The end of the Cold War and the dissolution of the Soviet Union in 1991 left the United States as the sole superpower. The U. S. is a member of the United Nations, World Bank, International Monetary Fund, Organization of American States. The United States is a developed country, with the worlds largest economy by nominal GDP. It ranks highly in several measures of performance, including average wage, human development, per capita GDP. While the U. S. economy is considered post-industrial, characterized by the dominance of services and knowledge economy, the United States is a prominent political and cultural force internationally, and a leader in scientific research and technological innovations. In 1507, the German cartographer Martin Waldseemüller produced a map on which he named the lands of the Western Hemisphere America after the Italian explorer and cartographer Amerigo Vespucci
5.
Penny (United States coin)
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The United States one-cent coin often called penny, is a unit of currency equaling one-hundredth of a United States dollar. Its obverse has featured the profile of President Abraham Lincoln since 1909, from 1959 to 2008, the reverse featured the Lincoln Memorial. Four different reverse designs in 2009 honored Lincolns 200th birthday and a new, the coin is 0.75 inches in diameter and 0.0598 inches in thickness. Its weight has varied, depending upon the composition of metals used in its production, Mints official name for the coin is cent and the U. S. Treasurys official name is one cent piece. The colloquial term penny derives from the British coin of the same name, in American English, pennies is the plural form. Although the coins abolition has been proposed because it is now very little. As of 2015, based on the U. S. Mint Annual Report released for 2014, it costs the U. S. Mint 1.67 cents to one cent because of the cost of materials, production. This figure includes the Mints fixed components for distribution and fabrication, fixed costs and overhead would have to be absorbed by other circulating coins without the penny. The loss from producing the one cent coin in the United States for the year of 2013 was $55,000,000 and this was a slight decrease from 2012, the year before, which had a production loss of $58,000,000. In honor of Lincolns 200th anniversary, special 2009 cents were minted for collectors in the composition as the 1909 coins. In 1943, at the peak of World War II, zinc-coated steel cents were made for a time because of war demands for copper. A few copper cents from 1943 were produced from the 1942 planchets remaining in the bins, similarly, some 1944 steel cents have been confirmed. During the early 1970s, the price of copper rose to the point where the cent contained almost one cents worth of copper and this led the Mint to test alternative metals, including aluminum and bronze-clad steel. Aluminum was chosen, and over 1.5 million of these pennies were struck, One aluminum cent was donated to the Smithsonian Institution. The cents composition was changed in 1982 because the value of the copper in the coin started to rise above one cent, some 1982 pennies used the 97. 5% zinc composition, while others used the 95% copper composition. With the exception of 2009 bicentennial cents minted specifically for collectors, in Fiscal Year 2013, the average one-cent piece minted cost the U. S. Mint 1.83 cents, down from 2.41 cents apiece in FY2011. The bronze and copper cents can be distinguished from the newer zinc cents by dropping the coins on a solid surface, the predominantly copper coins produce a higher-pitched ringing sound, while the zinc coins make a lower-pitched clunk. The coin has gone through several designs over its time frame
6.
Steel
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Steel is an alloy of iron and other elements, primarily carbon, that is widely used in construction and other applications because of its high tensile strength and low cost. Steels base metal is iron, which is able to take on two forms, body centered cubic and face centered cubic, depending on its temperature. It is the interaction of those allotropes with the elements, primarily carbon. In the body-centred cubic arrangement, there is an atom in the centre of each cube. Carbon, other elements, and inclusions within iron act as hardening agents that prevent the movement of dislocations that otherwise occur in the lattices of iron atoms. The carbon in steel alloys may contribute up to 2. 1% of its weight. Steels strength compared to pure iron is possible at the expense of irons ductility. With the invention of the Bessemer process in the mid-19th century and this was followed by Siemens-Martin process and then Gilchrist-Thomas process that refined the quality of steel. With their introductions, mild steel replaced wrought iron, further refinements in the process, such as basic oxygen steelmaking, largely replaced earlier methods by further lowering the cost of production and increasing the quality of the product. Today, steel is one of the most common materials in the world and it is a major component in buildings, infrastructure, tools, ships, automobiles, machines, appliances, and weapons. Modern steel is generally identified by various grades defined by assorted standards organizations, the noun steel originates from the Proto-Germanic adjective stakhlijan, which is related to stakhla. The carbon content of steel is between 0. 002% and 2. 1% by weight for plain iron–carbon alloys and these values vary depending on alloying elements such as manganese, chromium, nickel, iron, tungsten, carbon and so on. Basically, steel is an alloy that does not undergo eutectic reaction. In contrast, cast iron does undergo eutectic reaction, too little carbon content leaves iron quite soft, ductile, and weak. Carbon contents higher than those of steel make an alloy, commonly called pig iron, while iron alloyed with carbon is called carbon steel, alloy steel is steel to which other alloying elements have been intentionally added to modify the characteristics of steel. Common alloying elements include, manganese, nickel, chromium, molybdenum, boron, titanium, vanadium, tungsten, cobalt, and niobium. Additional elements are important in steel, phosphorus, sulfur, silicon, and traces of oxygen, nitrogen, and copper. Alloys with a higher than 2. 1% carbon content, depending on other element content, cast iron is not malleable even when hot, but it can be formed by casting as it has a lower melting point than steel and good castability properties
7.
Philadelphia Mint
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The Philadelphia Mint was created from the need to establish a national identity and the needs of commerce in the United States. This led the Founding Fathers of the United States to make an establishment of a national mint. The Coinage Act of 1792 was entered into law on April 2 and it proclaimed the creation of the United States Mint. Philadelphia at that time was the capital, therefore the first mint facility was built there. David Rittenhouse, an American scientist, was appointed the first director of the mint by President George Washington, two lots were purchased by Rittenhouse on July 18,1792, at Seventh Street and 631 Filbert Street in Philadelphia for $4,266.67. The next day, demolition of a whiskey distillery on the property began. Foundation work began on July 31, and by September 7, the smelt house was the first public building erected by the United States government. A three-story brick structure facing Seventh Street was constructed a few months later, measuring nearly 37 ft wide on the street, it only extended back 33 ft. The gold and silver for the mint were contained in basement vaults, the first floor housed deposit and weighing rooms, along with the press room, where striking coins took place. Mint official offices were on the floor, and the assay office was located on the third floor. A photograph of the Seventh Street building taken around 1908 show that by then the year 1792, between the smelt house and the building on Seventh Street, a mill house was built. Horses in the basement turned a mill located on the first floor. In January 1816, the smelt and mill houses were destroyed by a fire, the smelt house was never repaired and all smelting was done elsewhere. The mill house, which was destroyed, was soon replaced with a large brick building. It included a new engine in the basement to power the machinery. Until 1833, these three buildings provided the United States with hard currency, operations moved to the second Philadelphia mint in 1833, and the land housing the first mint was sold. In the late 19th or early 20th century, the property was sold to Frank Stewart, with no governmental help, the first mint was demolished between 1907 and 1911. Now, only a plaque remains to memorialize the spot
8.
San Francisco Mint
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The San Francisco Mint is a branch of the United States Mint and was opened in 1854 to serve the gold mines of the California Gold Rush. It quickly outgrew its first building and moved into a new one in 1874 and this building, the Old United States Mint, also known affectionately as The Granite Lady, is one of the few that survived the great 1906 San Francisco earthquake. It served until 1937, when the present facility was opened, within the first year of its operation, the San Francisco mint turned $4 million in gold bullion into coins. The second building, completed in 1874, was designed by Alfred B, mullett in a conservative Greek Revival style with a sober Doric order. Heroic efforts by Superintendent of the Mint, Frank A. Leach, and his men preserved the building, the mint resumed operation soon thereafter, continuing until 1937. In 1961 the Old Mint, as it had known, was designated a National Historic Landmark. It also became a California Historical Landmark in 1974, the given name of The Granite Lady is somewhat of a misnomer as most of the building is made from sandstone. While the base/basement of the building is made of granite, the entire external, the Granite Lady was a marketing term given in the 1970s that stuck. The Old Mint was open to visitors until 1993, in the fall of 2005, ground was broken for renovations that would turn the central court into a glass-enclosed galleria. In 2006 Congress created the San Francisco Old Mint Commemorative Coin, the first phase of renovations were completed in 2011. In 2014, the San Francisco Museum and Historical Society began raising money for the second phase, in 2015, the City of San Francisco looked for a new tenant to renovate and program the space with Activate San Francisco Events being selected as an interim tenant. Until a new tenant is found, the Old Mint will continue to be used for special events, in April 2016, the California Historical Society agreed to undertake the restoration of the building and its preservation as a public space. The new Mint was opened in 1937, beginning in 1955, circulating coinage from San Francisco was suspended for 13 years. In 1968, it took over most proof coinage production from the Philadelphia Mint, from 1975 to 2012, the San Francisco Mint has been used only for proof coinage, with the exception of the Susan B. Anthony dollar from 1979–81 and a portion of the mintage of cents in the early 1980s, the dollars bear a mintmark of an S, but the cents are otherwise indistinguishable from those minted at Philadelphia. In 2012, the San Francisco mint started to mint circulation strike quarters in the America the Beautiful quarter series, marked with an S mintmark and only issued for collectors. From 1962 to 1988, the San Francisco Mint was officially an assay office, the San Francisco Mint is located at 155 Hermann Street, but only admits visitors on rare exception. On May 15,1987, a number of people were allowed to tour the facility
9.
Zinc
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Zinc is a chemical element with the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table, in some respects zinc is chemically similar to magnesium, both elements exhibit only one normal oxidation state, and the Zn2+ and Mg2+ ions are of similar size. Zinc is the 24th most abundant element in Earths crust and has five stable isotopes, the most common zinc ore is sphalerite, a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States, Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity. Zinc metal was not produced on a large scale until the 12th century in India and was unknown to Europe until the end of the 16th century, the mines of Rajasthan have given definite evidence of zinc production going back to the 6th century BC. To date, the oldest evidence of pure zinc comes from Zawar, in Rajasthan, alchemists burned zinc in air to form what they called philosophers wool or white snow. The element was named by the alchemist Paracelsus after the German word Zinke. German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746, work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resistant zinc plating of iron is the application for zinc. Other applications are in batteries, small non-structural castings. A variety of compounds are commonly used, such as zinc carbonate and zinc gluconate, zinc chloride, zinc pyrithione, zinc sulfide. Zinc is an essential mineral perceived by the public today as being of exceptional biologic and public health importance, Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children, deficiency causes growth retardation, delayed sexual maturation, infection susceptibility, enzymes with a zinc atom in the reactive center are widespread in biochemistry, such as alcohol dehydrogenase in humans. Consumption of excess zinc can cause ataxia, lethargy and copper deficiency, Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish.6 pm. The metal is hard and brittle at most temperatures but becomes malleable between 100 and 150 °C, above 210 °C, the metal becomes brittle again and can be pulverized by beating. Zinc is a conductor of electricity. For a metal, zinc has relatively low melting and boiling points, the melting point is the lowest of all the transition metals aside from mercury and cadmium. Many alloys contain zinc, including brass, Other metals long known to form binary alloys with zinc are aluminium, antimony, bismuth, gold, iron, lead, mercury, silver, tin, magnesium, cobalt, nickel, tellurium, and sodium
10.
Copper
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Copper is a chemical element with symbol Cu and atomic number 29. It is a soft, malleable, and ductile metal with high thermal and electrical conductivity. A freshly exposed surface of copper has a reddish-orange color. Copper is one of the few metals that occur in nature in directly usable metallic form as opposed to needing extraction from an ore and this led to very early human use, from c.8000 BC. Copper used in buildings, usually for roofing, oxidizes to form a green verdigris, Copper is sometimes used in decorative art, both in its elemental metal form and in compounds as pigments. Copper compounds are used as agents, fungicides, and wood preservatives. Copper is essential to all living organisms as a trace dietary mineral because it is a key constituent of the enzyme complex cytochrome c oxidase. In molluscs and crustaceans, copper is a constituent of the blood pigment hemocyanin, replaced by the hemoglobin in fish. In humans, copper is found mainly in the liver, muscle, the adult body contains between 1.4 and 2.1 mg of copper per kilogram of body weight. The filled d-shells in these elements contribute little to interatomic interactions, unlike metals with incomplete d-shells, metallic bonds in copper are lacking a covalent character and are relatively weak. This observation explains the low hardness and high ductility of single crystals of copper, at the macroscopic scale, introduction of extended defects to the crystal lattice, such as grain boundaries, hinders flow of the material under applied stress, thereby increasing its hardness. For this reason, copper is supplied in a fine-grained polycrystalline form. The softness of copper partly explains its high conductivity and high thermal conductivity. The maximum permissible current density of copper in open air is approximately 3. 1×106 A/m2 of cross-sectional area, Copper is one of a few metallic elements with a natural color other than gray or silver. Pure copper is orange-red and acquires a reddish tarnish when exposed to air, as with other metals, if copper is put in contact with another metal, galvanic corrosion will occur. A green layer of verdigris can often be seen on old structures, such as the roofing of many older buildings. Copper tarnishes when exposed to sulfur compounds, with which it reacts to form various copper sulfides. There are 29 isotopes of copper, 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper, both have a spin of 3⁄2
11.
Ammunition
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Ammunition is the general term used for the material fired, scattered, dropped or detonated from any weapon. The term ammunition can be traced back to the mid 17th century, broadly speaking, ammunition refers to both expendable weapons and the component parts of other weapons that create the effect on a target. Nearly all weapons will require some form of ammunition to operate, the word comes from the French la munition, which refers to the material used for war. The terms ammunition and munitions are used interchangeably, although the term munition now usually refers to both the actual weapons system alongside the ammunition required to operate it. The purpose of ammunition is to project a force against a target to have an effect. The most iconic example of ammunition is the cartridge, which all components required to deliver the weapon effect in a single package. Ammunition comes in a range of sizes and types and is often designed to work only in specific weapons systems. However, there are internationally recognized standards for certain types that enable their use across different weapons. There are also types of ammunition that are designed to have a specialized effect on a target, such as armor-piercing shells and tracer ammunition. Ammunition is commonly colored in a manner to assist in the identification. A round is a cartridge containing a projectile, propellant, primer. A shell is a form of ammunition that is fired by a large cannon or artillery piece. Before the mid-19th century, these shells were made of solid materials. However, since that time, they are often filled with high-explosives. A shot refers to a release of a weapons system. This may involve firing just one round or piece of ammunition, a dud refers to loaded ammunition that fails to function as intended, typically failing to detonate on landing. However, it can refer to ammunition that fails to fire inside the weapon, known as a misfire, or when the ammunition only partially functions. Dud ammunition, which is classified as an ordnance, is regarded as highly dangerous
12.
Bronze
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These additions produce a range of alloys that may be harder than copper alone, or have other useful properties, such as stiffness, ductility, or machinability. The archeological period where bronze was the hardest metal in use is known as the Bronze Age. In the ancient Near East this began with the rise of Sumer in the 4th millennium BC, with India and China starting to use bronze around the same time, everywhere it gradually spread across regions. The Bronze Age was followed by the Iron Age starting from about 1300 BC and reaching most of Eurasia by about 500 BC, the discovery of bronze enabled people to create metal objects which were harder and more durable than previously possible. Bronze tools, weapons, armor, and building such as decorative tiles were harder and more durable than their stone. It was only later that tin was used, becoming the major ingredient of bronze in the late 3rd millennium BC. Tin bronze was superior to arsenic bronze in that the process could be more easily controlled. Also, unlike arsenic, metallic tin and fumes from tin refining are not toxic, the earliest tin-alloy bronze dates to 4500 BCE in a Vinča culture site in Pločnik. Other early examples date to the late 4th millennium BC in Africa, Susa and some ancient sites in China, Luristan, ores of copper and the far rarer tin are not often found together, so serious bronze work has always involved trade. Tin sources and trade in ancient times had a influence on the development of cultures. In Europe, a source of tin was the British deposits of ore in Cornwall. In many parts of the world, large hoards of bronze artefacts are found, suggesting that bronze also represented a store of value, in Europe, large hoards of bronze tools, typically socketed axes, are found, which mostly show no signs of wear. With Chinese ritual bronzes, which are documented in the inscriptions they carry and from other sources and these were made in enormous quantities for elite burials, and also used by the living for ritual offerings. Pure iron is soft, and the process of beating and folding sponge iron to wrought iron removes from the metal carbon. Careful control of the alloying and tempering eventually allowed for wrought iron with properties comparable to modern steel, Bronze was still used during the Iron Age, and has continued in use for many purposes to the modern day. Among other advantages, it does not rust, the weaker wrought iron was found to be sufficiently strong for many uses. Archaeologists suspect that a disruption of the tin trade precipitated the transition. The population migrations around 1200–1100 BC reduced the shipping of tin around the Mediterranean, limiting supplies, there are many different bronze alloys, but typically modern bronze is 88% copper and 12% tin
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