Acmonital (acronym of acciaio monetario italiano, meaning "Italian monetary steel" in Italian) is a stainless steel alloy consisting mostly of iron, with 0.14% carbon, 17.5-19% chromium, 0.50% magnesium, 1.15% silicon, 0.03% sulfur, and 0.03% phosphorus by weight. Acmonital was used for the Italian lira coins. [1]
An alloy is a mixture of chemical elements of which in most cases at least one is a metallic element, although it is also sometimes used for mixtures of elements; herein only metallic alloys are described. Most alloys are metallic and show good electrical conductivity, ductility, opacity, and luster, and may have properties that differ from those of the pure elements such as increased strength or hardness. In some cases, an alloy may reduce the overall cost of the material while preserving important properties. In other cases, the mixture imparts synergistic properties such as corrosion resistance or mechanical strength.
Bronze is an alloy consisting primarily of copper, commonly with about 12–12.5% tin and often with the addition of other metals and sometimes non-metals, such as phosphorus, or metalloids, such as arsenic or silicon. These additions produce a range of alloys that may be harder than copper alone, or have other useful properties, such as strength, ductility, or machinability.
A metal is a material that, when polished or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. These properties are all associated with having electrons available at the Fermi level, as against nonmetallic materials which do not. Metals are typically ductile and malleable.
Nickel is a chemical element; it has symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive, but large pieces are slow to react with air under standard conditions because a passivation layer of nickel oxide forms on the surface that prevents further corrosion. Even so, pure native nickel is found in Earth's crust only in tiny amounts, usually in ultramafic rocks, and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth's atmosphere.
There are eight euro coin denominations, ranging from one cent to two euros. The coins first came into use in 2002. They have a common reverse, portraying a map of Europe, but each country in the eurozone has its own design on the obverse, which means that each coin has a variety of different designs in circulation at once. Four European microstates that are not members of the European Union use the euro as their currency and also have the right to mint coins with their own designs on the obverse side.
1943 steel cents are U.S. one-cent coins that were struck in steel due to wartime shortages of copper. The Philadelphia, Denver, and San Francisco mints each produced these 1943 Lincoln cents. The unique composition of the coin has led to various nicknames, such as wartime cent, steel war penny, zinc cent and steelie. The 1943 steel cent features the same Victor David Brenner design for the Lincoln cent which had been in use since 1909.
Cupronickel or copper–nickel (CuNi) is an alloy of copper with nickel, usually along with small quantities of other elements added for strength, such as iron and manganese. The copper content typically varies from 60 to 90 percent.
Tool steel is any of various carbon steels and alloy steels that are particularly well-suited to be made into tools and tooling, including cutting tools, dies, hand tools, knives, and others. Their suitability comes from their distinctive hardness, resistance to abrasion and deformation, and their ability to hold a cutting edge at elevated temperatures. As a result, tool steels are suited for use in the shaping of other materials, as for example in cutting, machining, stamping, or forging.
The lira was the currency of Italy between 1861 and 2002. It was introduced by the Napoleonic Kingdom of Italy in 1807 at par with the French franc, and was subsequently adopted by the different states that would eventually form the Kingdom of Italy in 1861. It was subdivided into 100 centesimi, which means "hundredths" or "cents". The lira was also the currency of the Albanian Kingdom from 1941 to 1943.
The fineness of a precious metal object represents the weight of fine metal therein, in proportion to the total weight which includes alloying base metals and any impurities. Alloy metals are added to increase hardness and durability of coins and jewelry, alter colors, decrease the cost per weight, or avoid the cost of high-purity refinement. For example, copper is added to the precious metal silver to make a more durable alloy for use in coins, housewares and jewelry. Coin silver, which was used for making silver coins in the past, contains 90% silver and 10% copper, by mass. Sterling silver contains 92.5% silver and 7.5% of other metals, usually copper, by mass.
Coins of the Indian rupee (₹) were first minted in 1950. New coins have been produced annually since then and they make up a valuable aspect of the Indian currency system. Today, circulating coins exist in denominations of One Rupee, Two Rupees, Five Rupees, Ten Rupees and Twenty Rupees. All of these are produced by four mints located across India, in Kolkata, Mumbai, Hyderabad, Noida.
Gun metal, also known as red brass in the United States, is a type of bronze – an alloy of copper, tin, and zinc. Proportions vary but 88% copper, 8–10% tin, and 2–4% zinc is an approximation. Originally used chiefly for making guns, it has largely been replaced by steel for that purpose. Gunmetal casts and machines well, and is resistant to corrosion from steam and salt water. It is used to make steam and hydraulic castings, valves, gears, statues, and various small objects, such as buttons. It has a tensile strength of 221 megapascals (32,100 psi) to 310 megapascals (45,000 psi), a specific gravity of 8.7, a Brinell hardness of 65 to 74, and a melting point of around 1,000 degrees Celsius.
Aluminium bronze is a type of bronze in which aluminium is the main alloying metal added to copper, in contrast to standard bronze or brass. A variety of aluminium bronzes of differing compositions have found industrial use, with most ranging from 5% to 11% aluminium by weight, the remaining mass being copper; other alloying agents such as iron, nickel, manganese, and silicon are also sometimes added to aluminium bronzes.
Bi-metallic coins are coins consisting of two (bi-) metals or alloys, generally arranged with an outer ring around a contrasting center. Common circulating examples include the €1, €2, United Kingdom £1 and £2, Canadian $2, South Africa R5, Egyptian £1, Turkish 1 lira and 50 kurus, Indian ₹10 and ₹20, Indonesian Rp1,000, Polish 2 and 5 zł, Czech 50 Kč, Hungarian 100 and 200 Ft, Bulgarian 1 and 2 lv., Hong Kong $10, Argentine $1 and $2, Brazilian R$1, Chilean $100 and $500, Colombian $500 and $1000, Peruvian S/2 and S/5, Albanian 100 Lekë, Thai 10 baht and all Mexican coins of $1 or higher denomination.
Crown gold is a 22 karat (kt) gold alloy used in the crown coin introduced in England in 1526. In this alloy, the proportion of gold is 22 parts out of 24. Crown gold is appreciably less prone to wear than the softer 23 kt gold of earlier gold sovereigns — an important point for coins intended for everyday use in circulation.
Italma is an aluminium alloy. It was produced by A.S.A. and was introduced shortly after World War II in order to being used in the new coinage of the Italian lira, which lasted until the adoption of the Italian euro coins in 2002. It comprised 96.2% aluminium, 3.5% magnesium, and 0.3% manganese.
Group 11, by modern IUPAC numbering, is a group of chemical elements in the periodic table, consisting of copper (Cu), silver (Ag), gold (Au), and roentgenium (Rg), although no chemical experiments have yet been carried out to confirm that roentgenium behaves like the heavier homologue to gold. Group 11 is also known as the coinage metals, due to their usage in minting coins—while the rise in metal prices mean that silver and gold are no longer used for circulating currency, remaining in use for bullion, copper remains a common metal in coins to date, either in the form of copper clad coinage or as part of the cupronickel alloy. They were most likely the first three elements discovered. Copper, silver, and gold all occur naturally in elemental form.
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. Gold, silver and bronze or copper were the principal coinage metals of the ancient world, the medieval period and into the late modern period when the diversity of coinage metals increased. Coins are often made from more than one metal, either using alloys, coatings (cladding/plating) or bimetallic configurations. While coins are primarily made from metal, some non-metallic materials have also been used.