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Iridium compounds are used as catalysts in the Cativa process for carbonylation of methanol to produce acetic acid. [92] [93] Iridium complexes are often active for asymmetric hydrogenation both by traditional hydrogenation. [94] and transfer hydrogenation. [95] This property is the basis of the industrial route to the chiral herbicide (S ...
The type locality of this iridium anomaly is near Raton, New Mexico. [1] [2]Iridium is a very rare element in the Earth's crust, but is found in anomalously high concentrations (around 100 times greater than normal) in a thin worldwide layer of clay marking the boundary between the Cretaceous and Paleogene periods, 66 million years ago.
Other precious metals include the platinum group metals: ruthenium, rhodium, palladium, osmium, iridium, and platinum, of which platinum is the most widely traded. [1] The demand for precious metals is driven not only by their practical use but also by their role as investments and a store of value. Historically, precious metals have commanded ...
Iridium-192 (symbol 192 Ir) is a radioactive isotope of iridium, with a half-life of 73.83 days. [11] It decays by emitting beta (β) particles and gamma (γ) radiation. About 96% of 192 Ir decays occur via emission of β and γ radiation, leading to 192 Pt. Some of the β particles are captured by other 192 Ir nuclei, which are then converted ...
Osmiridium is a naturally occurring alloy of iridium and osmium found in platinum-bearing river sands in the Ural Mountains and in North and South America. Trace amounts of osmium also exist in nickel-bearing ores found in the Sudbury, Ontario, region along with other platinum group metals. Even though the quantity of platinum metals found in ...
While lists of noble metals can differ, they tend to cluster around gold and the six platinum group metals: ruthenium, rhodium, palladium, osmium, iridium, and platinum. In addition to this term's function as a compound noun , there are circumstances where noble is used as an adjective for the noun metal .
The same deposits of native copper on the Keweenaw Peninsula and Isle Royale were later mined commercially. From 1845 until 1887, the Michigan Copper Country was the leading producer of copper in the United States. Masses of native copper weighing hundreds of tons were sometimes found in the mines.
Osmiridium has been defined as containing a higher proportion of iridium, with iridosmine containing more osmium. However, as the content of the natural Os-Ir alloys varies considerably, the constituent percentages of specimens often reflects the reverse situation of osmiridium describing specimens containing a higher proportion of osmium and ...