What (who) is platinum-iridium - definition
ISOTOPES OF IRIDIUM
Ir 192m; Iridium-192; Ir-192; Iridium-164; Iridium-165; Iridium-166; Iridium-167; Iridium-168; Iridium-169; Iridium-170; Iridium-171; Iridium-172; Iridium-173; Iridium-174; Iridium-175; Iridium-176; Iridium-177; Iridium-178; Iridium-179; Iridium-180; Iridium-181; Iridium-182; Iridium-183; Iridium-184; Iridium-185; Iridium-186; Iridium-187; Iridium-188; Iridium-189; Iridium-190; Iridium-191; Iridium-193; Iridium-194; Iridium-195; Iridium-196; Iridium-197; Iridium-198; Iridium-199; Iridium isotopes; Iridium isotope
platinum-iridium
<standard> A standard, against which all others of the same
category are measured. Usage: silly.
The notion is that one of whatever it is has actually been
cast in platinum-iridium alloy and placed in the vault beside
the Standard Kilogram at the International Bureau of Weights
and Measures near Paris, as the bar defining the standard
metre once was.
"This garbage collection algorithm has been tested against
the platinum-iridium cons cell in Paris."
Compare golden.
[Jargon File ]
(1997-02-20)
Platinum group
![Replica of the [[NIST]] national prototype kilogram standard, made in 90% platinum - 10% iridium alloy](https://commons.wikimedia.org/wiki/Special:FilePath/National prototype kilogram K20 replica.jpg?width=200 "Replica of the [[NIST]] national prototype kilogram standard, made in 90% platinum - 10% iridium alloy")
SIX NOBLE, PRECIOUS METALLIC ELEMENTS CLUSTERED TOGETHER IN THE PERIODIC TABLE: RUTHENIUM, RHODIUM, PALLADIUM, OSMIUM, IRIDIUM, AND PLATINUM
Platinum family; Platinum Series; Platinum group metals; Platinum metals; Platinum group metal; Platinide; Platinum group elements; Platinoid; Platinum-group metal; Platinum-group metals; PGMs; Platinum-group
The platinum-group metals (abbreviated as the PGMs; alternatively, 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. These elements are all transition metals in the d-block (groups 8, 9, and 10, periods 5 and 6).
platinum metals
SIX NOBLE, PRECIOUS METALLIC ELEMENTS CLUSTERED TOGETHER IN THE PERIODIC TABLE: RUTHENIUM, RHODIUM, PALLADIUM, OSMIUM, IRIDIUM, AND PLATINUM
Platinum family; Platinum Series; Platinum group metals; Platinum metals; Platinum group metal; Platinide; Platinum group elements; Platinoid; Platinum-group metal; Platinum-group metals; PGMs; Platinum-group
¦ plural noun Chemistry the six metals platinum, palladium, ruthenium, osmium, rhodium, and iridium, which have similar properties and tend to occur together in nature.
Wikipedia
Isotopes of iridium
There are two natural isotopes of iridium (77Ir), and 37 radioisotopes, the most stable radioisotope being 192Ir with a half-life of 73.83 days, and many nuclear isomers, the most stable of which is 192m2Ir with a half-life of 241 years. All other isomers have half-lives under a year, most under a day. All isotopes of iridium are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed.
