The ignition system consists of a glow plug - hence the proper term glow engine - which has a coil of platinum containing wire alloy, usually platinum-iridium.
en.wikipedia.org The noble metals are most commonly considered to be ruthenium, rhodium, palladium, silver, osmium, iridium, platinum, and gold.
en.wikipedia.org A more convenient approach was used for the international prototype metre of 1870, a bar of platinum-iridium alloy which served as the definition of the meter from 1889 to 1960.
en.wikipedia.org The most common energy source used is radiofrequency energy delivered through the platinum-iridium tip of an ablation catheter.
jama.jamanetwork.com Iridium is found in nature as an uncombined element or in natural alloys; especially the iridiumosmium alloys, osmiridium (osmium-rich), and iridosmium (iridium-rich).
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