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The archaeological period during which bronze was the hardest metal in widespread use is known as the Bronze Age. The beginning of the Bronze Age in western Eurasia and India is conventionally dated to the mid-4th millennium BCE (~3500 BCE), and to the early 2nd millennium BCE in China; [ 1 ] elsewhere it gradually spread across regions.
Copper alloys are metal alloys that have copper as their principal component. They have high resistance against corrosion . Of the large number of different types, the best known traditional types are bronze , where tin is a significant addition, and brass , using zinc instead.
Hiduminium or R.R. alloys (2% copper, iron, nickel): used in aircraft pistons; Hydronalium (up to 12% magnesium, 1% manganese): used in shipbuilding, resists seawater corrosion; Italma (3.5% magnesium, 0.3% manganese): formerly used to make coinage of the Italian lira; Magnalium (5-50% magnesium): used in airplane bodies, ladders, pyrotechnics ...
Gunmetal ingot is a related alloy in which the zinc is replaced by 2% lead; this makes the alloy easier to cast but it has less strength. [2]Modified gunmetal contains lead in addition to the zinc; it is typically composed of 86% copper, 9.5% tin, 2.5% lead, and 2% zinc.
Italy pioneered the use for coinage of an aluminium-bronze alloy called bronzital (literally "Italian bronze") in its 5- and 10-centesimi from 1939. Its alloy was finalized in 1967 to 92% copper, 6% aluminium, and 2% nickel, [ 5 ] and was since used in the 20, 200 and 500 Italian Lira coins until 2001.
The coinage metals comprise those metallic chemical elements and alloys which have been used to mint coins. Historically, most coinage metals are from the three nonradioactive members of group 11 of the periodic table: copper, silver and gold. Copper is usually augmented with tin or other metals to form bronze.
Patina (/ p ə ˈ t iː n ə / pə-TEE-nə or / ˈ p æ t ɪ n ə / PAT-ih-nə) is a thin layer that variously forms on the surface of copper, brass, bronze, and similar metals and metal alloys (tarnish produced by oxidation or other chemical processes), or certain stones [1] and wooden furniture (sheen produced by age, wear, and polishing), or ...
Arsenical bronze is an alloy in which arsenic, as opposed to or in addition to tin or other constituent metals, is combined with copper to make bronze. The use of arsenic with copper, either as the secondary constituent or with another component such as tin, results in a stronger final product and better casting behavior.