Leaders of primary platinum production are South Africa and Russia, followed by Canada, Zimbabwe and USA. Platinum and palladium are also mined commercially from the Stillwater igneous complex in Montana, USA. South Africa, with vast platinum ore deposits in the Merensky Reef of the Bushveld complex, is the world's largest producer of platinum, followed by Russia. The huge quantities of nickel ore processed makes up for the fact that platinum makes up only two parts per million of the ore. Platinum is also produced commercially as a by-product of nickel ore processing. Platinum in a native state, often accompanied by small amounts of other platinum metals, is found in alluvial and placer deposits in Colombia, Ontario, the Ural Mountains, and in certain western American states. A naturally occurring platinum-iridium alloy, platiniridium, is found in the mineral cooperite (platinum sulfide, PtS). That said, Sperrylite (platinum arsenide, PtAs 2) ore is by far the most significant source of this metal. Platinum can occur as a native metal, but it can also occur in various different minerals and alloys. 10 g PGM/ton ore, thus the identity of the particular mineral is unknown. Other economically significant PGE deposits include mafic intrusions related to flood basalts, and ultramafic complexes of the Alaska, Urals type. Mafic layered intrusions, including the Bushveld Complex, outweigh by far all other geological settings of platinum deposits. Mafic and ultramafic igneous rocks host practically all primary PGM ore of the world. Geochemically anomalous traces occur predominantly in chromian spinels and sulfides. Generally, ultramafic and mafic igneous rocks have relatively high, and granites low, PGE trace content. ![]() VECs contain solid platinum (Pt), palladium (Pd), and rhodium (Rh) and are installed in the exhaust system of vehicles to reduce harmful emissions, such as carbon monoxide (CO), by converting them into less harmful emissions. Apart from their application in jewellery, platinum metals are also used in anticancer drugs, industries, dentistry, electronics, and vehicle exhaust catalysts (VECs). Other distinctive properties include resistance to chemical attack, excellent high-temperature characteristics, high mechanical strength, good ductility, and stable electrical properties. They are highly resistant to wear and tarnish, making platinum, in particular, well suited for fine jewellery. ![]() The platinum metals have many useful catalytic properties. Properties and uses Replica of the NIST national prototype kilogram standard, made in 90% platinum, 10% iridium alloy Significant uses of selected PGMs, 1996 PGM ![]() īy 1815, rhodium and palladium had been discovered by William Hyde Wollaston, and iridium and osmium by his close friend and collaborator Smithson Tennant. They regarded platinum as an unwanted impurity in the silver they were mining. The name platinum is derived from the Spanish word platina “little silver", the name given to the metal by Spanish settlers in Colombia. However, even though the metal was used by pre-Columbian peoples, the first European reference to platinum appears in 1557 in the writings of the Italian humanist Julius Caesar Scaliger (1484–1558) as a description of a mysterious metal found in Central American mines between Darién (Panama) and Mexico ("up until now impossible to melt by any of the Spanish arts"). Naturally occurring platinum and platinum-rich alloys were known by pre-Columbian Americans for many years. The three elements above the platinum group in the periodic table ( iron, nickel and cobalt) are all ferromagnetic these, together with the lanthanide element gadolinium (at temperatures below 20 ☌), are the only known transition metals that display ferromagnetism near room temperature. However, they can be further subdivided into the iridium-group platinum-group elements (IPGEs: Os, Ir, Ru) and the palladium-group platinum-group elements (PPGEs: Rh, Pt, Pd) based on their behaviour in geological systems. They have similar physical and chemical properties, and tend to occur together in the same mineral deposits. The six platinum-group metals are ruthenium, rhodium, palladium, osmium, iridium, and platinum. These elements are all transition metals in the d-block (groups 8, 9, and 10, periods 5 and 6). The platinum-group metals ( PGMs), also known as the platinoids, platinides, platidises, platinum group, platinum metals, platinum family or platinum-group elements ( PGEs), are six noble, precious metallic elements clustered together in the periodic table.
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