"cast bronze or brass issues. This concept was later adopted by Japan, Korea and Annam (Vietnam), and also influenced regions in South-East Asia. The Lydian coins consisted of discs or lumps of electrum (a natural gold/silver alloy), and were stamped on two sides with dies. This concept spread rapidly to neighbouring Greek city states in Asia Minor and across the Aegean Sea, and eventually throughout the Mediterranean. When Lydia was conquered by Achaemenid Persia, the production of Lydian coins continued in the guise of silver Siglos and gold Darics. Other parts of Persia only began to mint coins at the"
"metals still melt easily and, in addition, have unusually low boiling points. Gold has atoms with one less 6s electron than mercury. Those electrons are more easily removed and are shared between the gold atoms forming relatively strong metallic bonds. Zinc, cadmium and mercury form a large range of alloys. Among the zinc containing ones, brass is an alloy of zinc and copper. 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. While neither zinc nor zirconium are ferromagnetic, their alloy exhibits ferromagnetism"
"Elektron (alloy) Elektron is the registered trademark of a wide range of magnesium alloys manufactured by a British company Magnesium Elektron Limited. There are about 100 alloys in the Elektron range, containing from 0% to 9.5% of some of the following elements in varying proportions: aluminium (< 9.5%), yttrium (5.25%), neodymium (2.7%), silver (2.5%), gadolinium (1.3%), zinc (0.9%), zirconium (0.6%), manganese (0.5%) and other rare-earth metals. Varying amounts of alloying elements (up to 9.5%) added to the magnesium result in changes to mechanical properties such as increased tensile strength, creep resistance, thermal stability or corrosion resistance. Elektron is unusually light"
"Elektron (alloy) Elektron is the registered trademark of a wide range of magnesium alloys manufactured by a British company Magnesium Elektron Limited. There are about 100 alloys in the Elektron range, containing from 0% to 9.5% of some of the following elements in varying proportions: aluminium (< 9.5%), yttrium (5.25%), neodymium (2.7%), silver (2.5%), gadolinium (1.3%), zinc (0.9%), zirconium (0.6%), manganese (0.5%) and other rare-earth metals. Varying amounts of alloying elements (up to 9.5%) added to the magnesium result in changes to mechanical properties such as increased tensile strength, creep resistance, thermal stability or corrosion resistance. Elektron is unusually light"
"Aluminium alloy Aluminium alloys (or aluminum alloys; see spelling differences) are alloys in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon, tin and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories heat-treatable and non-heat-treatable. About 85% of aluminium is used for wrought products, for example rolled plate, foils and extrusions. Cast aluminium alloys yield cost-effective products due to the low melting point, although they generally have lower tensile strengths than wrought alloys. The most important cast aluminium alloy system"
"heavier metalloids continue the theme. Arsenic can form alloys with metals, including platinum and copper; it is also added to copper and its alloys to improve corrosion resistance and appears to confer the same benefit when added to magnesium. Antimony is well known as an alloy-former, including with the coinage metals. Its alloys include pewter (a tin alloy with up to 20% antimony) and type metal (a lead alloy with up to 25% antimony). Tellurium readily alloys with iron, as ferrotellurium (50–58% tellurium), and with copper, in the form of copper tellurium (40–50% tellurium). Ferrotellurium is used as a stabilizer"
"electrical contacts and the production of thick-film resistors. A minor application of ruthenium is its use in some platinum alloys. Rhodium is a chemical element that is a rare, silvery-white, hard, and chemically inert transition metal and a member of the platinum group. It has the chemical symbol Rh and atomic number 45. It is composed of only one isotope,Rh. Naturally occurring rhodium is found as the free metal, alloyed with similar metals, and never as a chemical compound. It is one of the rarest precious metals and one of the most costly (gold has since taken over the top"
"one or two properties very different from the expected norm, or that are otherwise notable. Sodium, potassium, rubidium, caesium, barium, platinum, gold Manganese Iron, cobalt, nickel, gadolinium, terbium, dysprosium, holmium, erbium, thulium Iridium Gold Mercury Lead Bismuth Uranium Plutonium Boron Boron, antimony Silicon Arsenic Antimony Hydrogen Helium Carbon Phosphorus Iodine Properties of metals, metalloids and nonmetals Metals appear lustrous (beneath any patina); form mixtures (alloys) when combined with other metals; tend to lose or share electrons when they react with other substances; and each forms at least one predominantly basic oxide. Most metals are silvery looking, high density, relatively soft"
"metal ingots were found in an ancient shipwreck in Gela (Sicily), which were made of an alloy primarily consisting of copper, zinc and small percentages of nickel, lead, and iron. In numismatics, orichalcum is the golden-colored bronze alloy used by the Roman Empire for their sestertius and dupondius coins. The name is derived from the Greek , ""oreikhalkos"" (from , ""oros,"" mountain and , ""chalkos,"" copper), meaning literally ""mountain copper"". The Romans transliterated ""orichalcum"" as ""aurichalcum,"" which was thought to literally mean ""gold copper"". It is known from the writings of Cicero that the metal which they called orichalcum resembled"
"Amalgam (chemistry) An amalgam is an alloy of mercury with another metal, which may be a liquid, a soft paste or a solid, depending upon the proportion of mercury. These alloys are formed through metallic bonding, with the electrostatic attractive force of the conduction electrons working to bind all the positively charged metal ions together into a crystal lattice structure. Almost all metals can form amalgams with mercury, the notable exceptions being iron, platinum, tungsten, and tantalum. Silver-mercury amalgams are important in dentistry, and gold-mercury amalgam is used in the extraction of gold from ore. Zinc amalgam finds use in"
"the most important being bronze, an alloy of copper and tin. Alloys are mixtures of different metals created either by smelting or by forging. It is important to note that an ore does not necessarily constitute an alloy; ore is a collection of minerals and alloyed metals. As metallurgical technology developed (hammering, melting, smelting, roasting, cupellation, moulding, smithing, etc.), more metals were intentionally included in the metallurgical repertoire. By the height of the Roman Empire, metals in use included: Gold, Silver, Copper, Tin, Lead, Zinc, Iron, Mercury, Arsenic, Antimony (Healy 1978). As in the Bronze Age, metals were used based"
"and copper concentration, although most useful alloys tend to be richer in silver than the eutectic mixture (71.9% silver and 28.1% copper by weight, and 60.1% silver and 28.1% copper by atom). Most other binary alloys are of little use: for example, silver–gold alloys are too soft and silver–cadmium alloys too toxic. Ternary alloys have much greater importance: dental amalgams are usually silver–tin–mercury alloys, silver–copper–gold alloys are very important in jewellery (usually on the gold-rich side) and have a vast range of hardnesses and colours, silver–copper–zinc alloys are useful as low-melting brazing alloys, and silver–cadmium–indium (involving three adjacent elements on"
"phase. The stable alkali metals are all silver-coloured metals except for caesium, which has a pale golden tint: it is one of only three metals that are clearly coloured (the other two being copper and gold). Additionally, the heavy alkaline earth metals calcium, strontium, and barium, as well as the divalent lanthanides europium and ytterbium, are pale yellow, though the colour is much less prominent than it is for caesium. Their lustre tarnishes rapidly in air due to oxidation. They all crystallise in the body-centered cubic crystal structure, and have distinctive flame colours because their outer s electron is very"
"more reactive than gold. Natural alloys of the platinum group metals include: native osmium (Os,Ir,Ru), rutheniridosmine (Ir,Os,Ru), ruthenium (Ru,Ir), palladium (Pd,Pt), platinum Pt, and rhodium (Rh,Pt). In addition gold, copper, iron, mercury, tin and lead may occur in alloys of this group. As with gold, salts and other compounds of the platinum group metals are rare; native platinum and related metals and alloys are the predominant minerals bearing these metals. These metals occur associated with ultramafic intrusions and placer deposits derived from those intrusions. Native copper has been historically mined as an early source of the metal. The term Old"
"Titanium gold In metallurgy, titanium gold (Ti-Au or Au-Ti) refers to an alloy consisting of titanium and gold. Such alloys are used in dentistry, ceramics and jewelry. Like many other alloys, titanium gold alloys have a higher yield strength, tensile strength, hardness, and magnetism than either of its constituent metals. In July 2016, researchers have discovered that a titanium-gold alloy, β-TiAu (strictly speaking, an intermetallic), is up to 4 times harder than titanium. In the 2008 film Iron Man (2008 film), the title character wears an armor made from a titanium-gold alloy. According to actor Robert Downey Jr., who played"
"or more of the following other than titanium in varying amounts. These are molybdenum, vanadium, niobium, tantalum, zirconium, manganese, iron, chromium, cobalt, nickel, and copper. The titanium alloys have excellent formability and can be easily welded. Beta titanium is nowadays largely utilized in the orthodontic field and was adopted for orthodontics use in the 1980s. This type of alloy replaced stainless steel for certain uses, as stainless steel had dominated orthodontics since the 1960s. It has strength/modulus of elasticity ratios almost twice those of 18-8 austenitic stainless steel, larger elastic deflections in springs, and reduced force per unit displacement 2.2"
"Aluminium Aluminium or aluminum is a chemical element with symbol Al and atomic number 13. It is a silvery-white, soft, nonmagnetic and ductile metal in the boron group. By mass, aluminium makes up about 8% of the Earth's crust; it is the third most abundant element after oxygen and silicon and the most abundant metal in the crust, though it is less common in the mantle below. The chief ore of aluminium is bauxite. Aluminium metal is so chemically reactive that native specimens are rare and limited to extreme reducing environments. Instead, it is found combined in over 270 different"
"usually machined and faceted to be used as a ""gem"" in conventional jewelry rather than by itself. At a lower content of gold, the material is composed of the intermetallic and an aluminium-rich solid solution phase. At a higher content of gold, the gold-richer intermetallic AuAl forms; the purple color is preserved to about 15% of aluminium. At 88% of gold the material is composed of AuAl and changes color. The actual composition of AuAl is closer to AlAu as the sublattice is incompletely occupied. Blue gold is an alloy of gold and either gallium or indium. Gold-indium contains 46%"
"stereochemically active inert pair in thallium. The group 11 metals (or coinage metals), copper, silver, and gold, are typically categorised as transition metals given they can form ions with incomplete d-shells. Physically, they have the relatively low melting points and high electronegativity values associated with post-transition metals. ""The filled ""d"" subshell and free ""s"" electron of Cu, Ag, and Au contribute to their high electrical and thermal conductivity. Transition metals to the left of group 11 experience interactions between ""s"" electrons and the partially filled ""d"" subshell that lower electron mobility."" Chemically, the group 11 metals behave like main-group metals"
"antimony, and bismuth. Native chromium has been found in small grains in Sichuan, China and other locations. 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, rhenium, selenium, tantalum, tellurium, tin, titanium, tungsten, vanadium, and zinc, as well as two groups of metals: the gold group, and the platinum group. The gold group consists of gold, copper, lead, aluminium, mercury, and silver. The platinum group consists"
"Aluminium–lithium alloy Aluminium–lithium alloys (Al–Li) are a series of alloys of aluminium and lithium, often also including copper and zirconium. Since lithium is the least dense elemental metal, these alloys are significantly less dense than aluminium. Commercial Al–Li alloys contain up to 2.45% by mass of lithium. Alloying with lithium reduces structural mass by three effects: The crystal structure for AlLi and Al–Li, while based on the FCC crystal system, are very different. AlLi shows almost the same-size lattice structure as pure aluminium, except that lithium atoms are present in the corners of the unit cell. The AlLi structure is"
"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, rhenium, selenium, tantalum, tellurium, tin, titanium, tungsten, vanadium, and zinc, as well as two groups of metals: the gold group, and the platinum group. The gold group consists of gold, copper, lead, aluminium, mercury, and silver. The platinum group consists of platinum, iridium, osmium, palladium, rhodium, and ruthenium. Amongst the alloys found in native state have been"
"same alloy, made of 84–85% gold, 5–7% silver, and 8–10% copper, suggesting a contemporary construction of the main part of the crown, while the fillets external to the enamel plates and the hinge pins were made of 90–91% gold and 9–10% silver, suggesting subsequent reworking. Three of the twenty-four vitreous enamel plates are visually different from the others in colour and construction, and were traditionally considered to be later restorations. The XRF analysis confirmed that they were made with a different technique, with their glass being made of potassium salt, while the others are made of sodium salt (sodium is"
"Tantalum Tantalum is a chemical element with symbol Ta and atomic number 73. Previously known as ""tantalium"", its name comes from ""Tantalus"", a villain from Greek mythology. Tantalum is a rare, hard, blue-gray, lustrous transition metal that is highly corrosion-resistant. It is part of the refractory metals group, which are widely used as minor components in alloys. The chemical inertness of tantalum makes it a valuable substance for laboratory equipment and a substitute for platinum. Its main use today is in tantalum capacitors in electronic equipment such as mobile phones, DVD players, video game systems and computers. Tantalum, always together"
"the materials. Conventional amalgam alloy commonly consists of silver (~65% ), tin (~29%), copper (~8%) and other trace metals; current amalgam alloy consists of silver (40%), tin (32%), copper (30%) and other metals. To fabricate an amalgam filling, the dentist uses a mixing device to blend roughly equal parts (by mass) of shavings of a silver-base alloy with mercury until the shavings are thoroughly wetted. The silver alloy is typically 40–70% Ag, 25-29% Sn, 2–40% Cu and 0–2% Zn (when the alloy is formulated. Zn is a scavenger and is mostly consumed during melting and lost as oxide). The dentist"
"gold, indium, lithium, manganese, nickel, niobium, palladium, platinum, rhodium, ruthenium, selenium, silver, tantalum, terbium, thorium, titanium, vanadium, and yttrium. Almost all electronics contain lead and tin (as solder) and copper (as wire and printed circuit board tracks), though the use of lead-free solder is now spreading rapidly. The following are ordinary applications: Residents living around the e-waste recycling sites, even if they do not involve in e-waste recycling activities, can also face the environmental exposure due to the food, water, and environmental contamination caused by e-waste, because they can easily contact to e-waste contaminated air, water, soil, dust, and food"
"(to illustrate, tellurium is only about as abundant as platinum). The most metallic chalcophile elements (of the copper, zinc and boron groups) may mix to some degree with iron in the Earth's core. They are not likely to be depleted on Earth as a whole relative to their solar abundances since they do not form volatile hydrides. Zinc and gallium are somewhat ""lithophile"" in nature because they often occur in silicate or related minerals and form quite strong bonds with oxygen. Gallium, notably, is sourced mainly from bauxite, an aluminum hydroxide ore in which gallium ion substitutes for chemically similar"
"was its ability to form compounds with hydrogen. Under these conditions, the s- and f-block metals were strongly enriched during the formation of the Earth. The most enriched elements are rubidium, strontium and barium, which between them account for over 50 percent by mass of all elements heavier than iron in the Earth's crust. The nonmetallic lithophiles – phosphorus and the halogens – exist on Earth as ionic salts with s-block metals in pegmatites and seawater. With the exception of fluorine, whose hydride forms hydrogen bonds and is therefore of relatively low volatility, these elements have had their concentrations on"
"magnesium. Copper alloys have been known for a long time (since the Bronze Age), while the alloys of the other three metals have been relatively recently developed. Due to the chemical reactivity of these metals, the electrolytic extraction processes required were only developed relatively recently. The alloys of aluminium, titanium and magnesium are also known and valued for their high strength-to-weight ratios and, in the case of magnesium, their ability to provide electromagnetic shielding. These materials are ideal for situations where high strength-to-weight ratios are more important than bulk cost, such as in the aerospace industry and certain automotive engineering"
"material called electrum, a variable mix of gold and silver (with about 54% gold and 44% silver), and were in use in Lydia and surrounding areas for about 80 years. The unpredictability of its composition implied that it had a variable value, which greatly hampered its development. The earliest coins are mostly associated with Iron Age Anatolia, especially with the kingdom of Lydia. Early electrum coins were not standardized in weight, and in their earliest stage may have been ritual objects, such as badges or medals, issued by priests. Many early Lydian and Greek coins were minted under the authority"
"Mischmetal Mischmetal (from – ""mixed metal"") is an alloy of rare-earth elements. It is also called cerium mischmetal, or rare-earth mischmetal. A typical composition includes approximately55% cerium, 25% lanthanum, and 15-18% neodymium with other rare earth metals following. Its most common use is in the pyrophoric ferrocerium ""flint"" ignition device of many lighters and torches, although an alloy of only rare-earth elements would be too soft to give good sparks. For this purpose, it is blended with iron oxide and magnesium oxide to form a harder material known as ferrocerium. In chemical formulae it is commonly abbreviated as Mm, e.g."
"fresh mineral waters. ""Aluminium"" (symbol Al) or ""aluminum"" (American English) is a silvery white member of the boron group of chemical elements and a post-transition metal. It is not soluble in water under normal circumstances. Aluminium is the third most abundant element (after oxygen and silicon), and the most abundant metal, in the Earth's crust. It makes up about 8% by weight of the Earth's solid surface. Aluminium metal is too reactive chemically to occur natively. Instead, it is found combined in over 270 different minerals. The chief ore of aluminium is bauxite. Aluminium is remarkable for the metal's low"
"Gum metal Gum metal, also called TNTZ, is a unique titanium alloy with high elasticity, ductility, and yield strength. While originally developed with a composition of 23% niobium, 0.7% tantalum, 2% zirconium, and 1% oxygen, it can exist over a range of compositions and also include vanadium and hafnium. Applying cold work to gum metal actually decreases its elastic modulus, with reported shear moduli as low as . At the same time, cold work increases gum metal's yield strength. By using a heat treatment after this cold work, some elasticity can be sacrificed for even greater strength, with yield strengths"