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Article changed over to new Wikipedia:WikiProject Elements format by maveric149. Elementbox converted 11:33, 14 July 2005 by Femto (previous revision was that of 19:00, 31 May 2005).

Information Sources[edit]

Some of the text in this entry was rewritten from Los Alamos National Laboratory - Iridium. Additional text was taken directly from the Elements database 20001107 (via, Webster's Revised Unabridged Dictionary (1913) (via and WordNet (r) 1.7 (via Data for the table were obtained from the sources listed on the subject page and Wikipedia:WikiProject Elements but were reformatted and converted into SI units.


Some said the Iridium satellites had to be destroyed as mandated by the Bankrupcy court. Who can verify if they were destroyed or adopted by DoD?

They were to be decommissioned (allowed to drop out of orbit and burn up - might have been impressive to see the "iridium flares") but the network was purchased by the DOD in mid-2001 I believe (someone needs to do the research). --Justfred

I know they were not destroyed, tho who got them escaped me. But i'm pretty sure the bankruptcy court gave no order remotely resembling that. The press accounts left me with no doubt that the supposed plan, not to let them "drop" but to intentionally order them to do so within a short time (days), was a bluff by the owners in trying to flush out some buyer that they imagined was willing to bid higher on them than when the potential buyers believed time was on their side. --Jerzy(t) 23:33, 2004 Mar 4 (UTC)

6 December 2002: Is there or isn't there a country called Iridium??? I am going through and editing all the country pages, and found 'Iridium' in my list of countries... can someone clarify this for me? - User:Mark Ryan

I've never heard of such a nation. Neither has (which has all CIA Factbook data in it). --Dan

It's in my current White Pages phone book in the international calling codes - apparently you dial 881 then 6 to phone that country. - User:Mark Ryan

OK, I just found out the answer. The international calling code 881 isn't reserved for a country called Iridium, it's for the satellite mobile network of the same name!!! lol I can't believe I didn't realise that right away. I feel stupid. - User:Mark Ryan

Ir and Dinosaurs[edit]

"Iridium is notable for being the most corrosion resistant element known and for its association with the demise of the dinosaurs. "

What's the connection??

See Cretaceous-Tertiary extinction event and look for "iridium". This is already explained in this article, however. --mav 09:00, 21 Jan 2004 (UTC)
Wait a minute, i thot they had found fossils with iridium-lined prosthetic hip joints.... --Jerzy(t) 23:33, 2004 Mar 4 (UTC)

There's no connection. There's are hypothesis that dinosaurs are extincted because of a meteorite. Iridium is a molecule in meteorites. Evidence is that they found a hugh amount of Iridium at some places on earth. They think a meteorite caused dinosaurs extincting. —Preceding unsigned comment added by (talk) 17:12, 28 February 2008 (UTC)


I think there's some confusion here. Iridium is actually used (along with osmium and platinum) for tipping fountain pen nibs, not to make ballpoint balls. (Error may have crept in from misinterpreting Los Alamos page.)

iridium windows?[edit]

to protect radioactive sources? - Omegatron 22:38, Feb 4, 2005 (UTC)

Apparent typo on density[edit]

The density of this element is only slightly lower than that of osmium, which is generally considered to be the heaviest element known. However, calculations of density from the space lattice may produce more reliable data for these elements than actual measurements and give a density of 22650 kg/m³ for iridium versus 22661 kg/m³ for osmium. Definitive selection between the two is therefore not possible at this time.

This paragraph doesn't exactly make sense. It reads as if there's some uncertainty, but it seems to say that osmium is denser both experimentally and theoretically.

Yet density of Osmium given at Osmium as well as at Web Elements is 22.61 x 10^3 kg/m^-3, (not 22661) meaning that the wiki has a typo (which was apparently carried over from a typo at Los Alamos National Labs. Moreover, unless someone has a better source, it doesn't look like the actual precision of the calculation goes to the nearest kg/m^-3.

So that's why I'm editing the page. (I was just looking for some pretty pictures of the rainbow colors, man. Where's the party?)

--Munge 05:54, 8 Apr 2005 (UTC)

In addition, 22,650 kg per cubic meter is inconsistent with the value of 22.42  g·cm−3 given in the tabular summary for iridium.

--LexCon 14:17, 8 Nov 2007 (ET)

--TrinaLovesInfo 14:05, 7 Dec 2014 (CST)

There's a continuing contradiction in the story re. the relative densities of the two elements. They're the ones referenced with 3 and 9. I use Wikipedia a lot but have never edited, & am more a copy editor than a science person, so I'll leave this to someone with more expertise to address it.

Decimal point[edit]

Should the isotopes data use the English decimal point instead of the comma? 13:53, 11 December 2005 (UTC) -- Yes. done Femto 13:33, 12 December 2005 (UTC)

Iridium radioactivity scare in Venezuela[edit]


iridium compounds should be considered highly toxic. Is this a roundabout way of saying that the compounds are highly toxic? Markyour words 19:37, 24 February 2006 (UTC)

This is rather saying "We don't know, but don't blame us if your health is affected." Icek 04:51, 9 October 2006 (UTC)
I think this is saying that one should be careful for the reason that no definitive studies have been done on the toxicity of Iridium compounds. I will say that the only one I was ever wary of was the anhydrous trichloride. Drrocket 18:54, 17 November 2006 (UTC)

Corrosion resistance?[edit]

"Iridium is the most corrosion-resistant metal known. Iridium cannot be attacked by any acids or by aqua regia, but it can be attacked by molten salts, such as NaCl and NaCN."

Why is it that iridium is corroded by molten salts of sodium when sodium is a more reactive metal than iridium? —The preceding unsigned comment was added by (talk) 02:38, 23 February 2007 (UTC).

That would be why. Besides, molten salt is pretty vicious stuff. Michaelbusch 04:09, 23 February 2007 (UTC)

what about GOLD? Lx 121 (talk) 12:31, 21 June 2009 (UTC)

Yes man.You are correct.Iridium is the most corrosion resistant metal since it is the least reactive metal. --Sabbarish (talk) 13:41, 3 November 2013 (UTC)

Densest element or densest substance?[edit]

Apart from the Osmium/Iridium question, are these only the densest pure elements or also the densest substances (including compounds, mixtures and alloys) at normal Earth conditions? -- 12:38, 24 March 2007 (UTC)

I'm not sure where you guys got this from. Iridium isn't even close to the densest element that naturally exists on Earth. What about, say, Uranium? Are we talking about atomic density, or how closely packed together the atoms are? Gopher65 (talk) 19:11, 1 March 2008 (UTC)

Hmmm. I just looked it up and it is actually denser than uranium (per cubic cm anyway). Still, I think that line (and most of the rest of the article:P) could use clarification and... sourcification, if that's a word:).Gopher65 (talk) 19:19, 1 March 2008 (UTC)

The website claims that its density is 22.42 g/cubic cm and that its "calculated" density is 22650 kg/cubic meter. The latter is greater by ~ 1%, making it denser than osmium. This doesn't seem to make sense, as accurate weight/size measurements should be much better than 1 part in 100, unless the "calculation" is faulty somehow. Pierrecurie (talk) 10:06, 24 August 2008 (UTC)

I direct you down this page a few paragraphs to Talk:Iridium#clarification_of_density, where someone explained that "calculated" is actually measured as well, just by a different method :). Gopher65talk 01:48, 25 August 2008 (UTC)

Photographs of Iridium Salts[edit]

Are there any pictures of the "rainbow" coloured salts Ir gets its name from? Icetigris 19:13, 1 May 2007 (UTC)

what is the value of iridium (osmium is to exspensive for me ($25,000pergram))[edit]

is it true —Preceding unsigned comment added by (talk) 14:34, 28 March 2010 (UTC)

Iridium in Novel[edit]

A meteorite containing iridium is a device used in a Clive Cussler novel 'Sacred Stone'. It is apparently extremely radioactive but this seems to be at odds with the Wikipedia description of the element's properties.

See: 11:29, 6 August 2007 (UTC)

OK. So add that tidbit to the article on the novel. Doesn't seem notable for this article - just more trivia junk. Vsmith 13:37, 6 August 2007 (UTC)

Luis Alvarez and K-T event impact crater[edit]

This sentence is not entirely correct and has been rewritten: "A team led by Luis Alvarez (1980) proposed an extraterrestrial origin for this iridium, attributing it to an asteroid or comet impact near what is now Yucatán Peninsula." The Alvarez team did not know in 1980 where the impact crater was. It was not until 1990 that the Chicxulub crater was identified by other researchers who analyzed oil company exploration data; see the Cretaceous-Tertiary extinction event article. Piperh 21:21, 13 August 2007 (UTC)

Conflict of facts[edit]

According to the Irridium page, Irridium "Cannot be attacked by aqua regia" however,assuming that "attacked" means dissolved, then there is a problem; according to aqua regia, the mixture is named thusly because it can dissolve noble metals including Irridum. I don't know which statement is true, so I will change neither, but I am putting this information up on the aqua regia page as well.

Digressionfromatanget (talk) 23:10, 26 February 2008 (UTC)digressionfromatangent

Iridium hadn't been discovered when aqua regia got its name.--Syd Henderson (talk) 22:21, 21 June 2009 (UTC)

Iridium Lenses[edit]

Iridium is also used as a coating on goggles and sunglasses for reducing glare and improving contrast. I was looking for more information on it because there are different types of iridium lenses, but didn't find much besides product descriptions. If product descriptions were good enough, I wouldn't be trying to look it up. haha. —Preceding unsigned comment added by (talk) 00:51, 23 May 2008 (UTC)

clarification of density[edit]

Why would the calculated density be more accurate than the measured one? Does that make any sense? —Preceding unsigned comment added by (talk) 00:03, 9 July 2008 (UTC)

I have no idea. I can speculate though that it is because making a sample 100% pure is impossible in practise. So the measured value is actually the density of 99.99999999999(etc)% pure iridium, not pure iridium. That would throw the measured value off by just a smidgen. Gopher65talk 05:11, 9 July 2008 (UTC)
The "calculated" density in question is really measured too, just by a different, more indirect method. This method allows you to measure the density of the tiny unit cell of the crystal with better accuracy than you can measure the density directly on a macroscopic sample. My guess is that the very high melting point of iridium causes practical difficulties for producing a nice and pure solid that can be used to measure the density directly. --Itub (talk) 10:58, 9 July 2008 (UTC)


"Iridium is one of the rarest non-radioactive, non-noble gas elements in the Earth's crust,". Iridium is a gas? Oh, it is not as rare as some of the non-noble-gas elements. Anyway this sentence is confusing. How about: "There are few elements that are more rare than iridium. They are e1, e2, e3, etc". Or something like that. c.pergiel —Preceding unsigned comment added by (talk) 18:40, 12 July 2008 (UTC)

Fixed. I rewrote that paragraph to be a little bit clearer than it had been. Gopher65talk 16:42, 13 July 2008 (UTC)

"is 4 times less abundant than gold, 10 times less abundant than platinum" This is wrong; platinum is scarcer than gold. Please fix or delete. (talk) 04:01, 25 September 2008 (UTC)

The source that is cited says 0.01 ppm for Pt and 0.004 ppm for gold. What is your source? --Itub (talk) 05:06, 25 September 2008 (UTC)
"Platinum is an extremely rare metal, occurring as only 0.003 ppb in the Earth's crust, and is 30 times rarer than gold. It is sometimes mistaken for silver (Ag) but platinum is much whiter in appearence." That's from the Platinum article. So either it is wrong or your source is wrong... to frame it positively, one of them needs fixed or deleted. (talk) 05:15, 27 September 2008 (UTC)
The platinum article is probably wrong by three orders of magnitude (ppm instead of ppb) and does not cite a source. It is true, however, that many different values have been published and there is considerable variation among them. You can find several at Abundances of the elements (data page) and Abundance of elements in Earth's crust (the latter is based on websites, so one would have to check further to see what sources they used). You'll see that all of them have platinum as more abundant than gold, although in some cases the two elements have very similar abundances and in others they differ by a factor of 10.
I think the misconception that platinum is much less abundant than gold occurs because platinum is produced in much smaller amounts. But this is because gold is easier to find in high concentration, despite having a lower average abundance. --Itub (talk) 07:09, 27 September 2008 (UTC)
Fixed the total abundance issue by a single picture with sources. --Sabbarish (talk) 03:46, 7 October 2013 (UTC)

Osmium is less common in the Earth's crust than any of the elements listed. I am adding it to the list. -Athaler (talk) 15:09, 22 September 2014 (UTC)

Not according to everyone – the Rubber Bible (85th ed.) and Greenwood & Earnshaw disagree. Probably better to be vague about which elements are rarer than Ir: I edited it to be vague and only say that Ir is one of the nine rarest STABLE elements in the crust (you need the "stable", or you get into all sorts of problems with elements like technetium). Double sharp (talk) 09:15, 23 September 2014 (UTC)

Color inconsistency[edit]

The article and its references do not consistently describe the color of pure iridium.

  • Yellow: Found in Characteristics, backed up by the CRC Handbook of Physics and Chemistry.
  • Silver: Found in Intro and Infobox, backed up by Handbook of Inorganic Compounds, Dictionary of Inorganic Compounds, and Chemistry Foundations and Applications.

Unless someone can find a good source that backs up the yellow color, I'm inclined to go with silver, especially since the sample in the infobox is silver. While iridium may very well take on both appearances (its colorful salts certainly show this is possible), it is deceiving to state both are true in different sections without acknowledging the color. If iridium can be either color, we should try to find a source that states this explicitly, and hopefully explains why. --Cryptic C62 · Talk 15:36, 19 September 2008 (UTC)

The article currently describes it as "white, resembling platinum, but with a slight yellowish cast". I think that explains the subjectivity. It is certainly not as yellow as gold, as one can see from the pictures, but maybe if you could see samples of platinum and iridium side by side, the tints would looks slightly different. --Itub (talk) 15:44, 19 September 2008 (UTC)

App's - IMHO analysis[edit]

Following this strong lede: "The global demand for iridium in 2007 was 119,000 troy ounces (3,700 kg), out of which 25,000 oz (780 kg) were used for electrical applications such as spark plugs, 34,000 oz (1,100 kg) for electrochemical applications such as electrodes for the chloralkali process, 24,000 oz (750 kg) for catalysis, and 36,000 oz (1,100 kg) for other uses." The remainder of the section merits re-evaluation:

  • Probably "minor" or "other": "multi-pored spinnerets.."
  • "Iridium is also used as a hardening agent ..." I guess this is the pen nib bit.
  • Apparently real: "...high-temp... spark plugs"
  • An anectdote/testimony to oxidative stability, but hardly an app (unless we make a lot of these bars!): "International Meter bar ... standard of mass."
  • Interesting, but an application?: "radioisotope thermoelectric generators .."
  • probably big (see consumption data) but not on the main list: "Cativa process"
  • the following are quite minor or under study (WE tends to over-credit research-prayer-hope as being an app): "radiography source," "C-H activation" (no commercial process), "Ir(mppy)3" (no commercial device uses Ir, despite many papers).
  • An application - well I guess high-energy physics exps use a few mg of anything: "the production of antimatter.."

Otherwise, a nicely evolving article, my comments are well-intentioned, not criticism.--Smokefoot (talk) 05:00, 20 September 2008 (UTC)

Thank you for the comments. That section has been evolving from a disorganized bullet list into prose and is still unfinished. Yet I'm not sure if we have the same in mind for the scope of the "applications" section. Apparently you think of it only as commercial applications consuming significant amounts of iridium. I tend to think of it as a combination of commercial applications plus other interesting uses, even if just academic, historical, or even unique. Hence the inclusion of C-H activation, space probes, and the meter bar. However, I do hope to make more clear how significant each use is in terms of volume. And one could certainly make an argument for moving the meter bar and the space probes to the History section instead. --Itub (talk) 05:34, 20 September 2008 (UTC)
Right. The meter is more history but it was´one of the first real applications and the smeltering and casting of the thing at that time was a major technical improvment. The RTGs and the high energy physics only need a few kg, but for an element which is not produced and used in large quantities it is worth mentioning. Reorganisation under Subheadings might be a step to get it more organized.--Stone (talk) 07:31, 20 September 2008 (UTC)

occurence, production, apps refs[edit]

Nergaal (talk) 00:10, 21 September 2008 (UTC)

still needed[edit]

  • perhaps too much emphasis on the K-T boundary in the intro?
  • having one example for each oxidation state (especially -1 and +1) maybe some refs?
  • change all the masses to SI units
  • expand on the extreme characteristics — hardness especially: why is it so hard, and give some relative examples (on multiple scales)
  • cleanupcopyedit uses
  • expand precautions a bit (heavy metal?)
  • "produced in the Western world" => ha?
  • use has a number of entries that could be moved to the organoiridium compounds paragraph
  • cleanup the isotopes section of the infobox: add 188, 192m→192m2

Gtg so I will work on these a bit later. Nergaal (talk) 00:56, 21 September 2008 (UTC)

about the tags: if the refs actually cover more than one sentence, I still think they should be added if they say something like "is found only...", "is the most..." ; otherwise just delete the tags. Nergaal (talk) 07:15, 21 September 2008 (UTC)
I've thought about the K-T boundary in the intro, but thought it was interesting and it is the only context in which many people have heard of iridium, so I think it needs to be included. Perhaps it could be merged into the first paragraph, but I think it is fine as a separate paragraph.
I did not mind it, but it seemed a bit too long compared to other things there. Nergaal (talk) 09:15, 21 September 2008 (UTC)
SI units. If you are referring to the troy ounces, I don't think it is a good idea to change them (but conversions can be added where they are missing). That is the unit used in the industry (and in the references cited!) and part of "educating" the reader is showing them that. In articles about petroleum prices, we use barrels of oil, not cubic meters.
Come on, this is ridiculous! Believe me, 99.9% of the world outside US and UK have no idea what troy ounce is. All the other element prices are per g/kg. Also, this article is not about the industry of Ir, but about the element itself. Why do you think the infoboxes use "real units" not such pseudo-units. Nergaal (talk) 09:13, 21 September 2008 (UTC)
You are both right. The unit used in the references plus a translation for the people who do not want to learn a system dead in the rest of the world since Napoleon hit it hard on the head wit the platinum-iridium Metre.--Stone (talk) 09:33, 21 September 2008 (UTC)
This article is about all aspects of iridium, including economics an history, not only chemistry. Most people in the UK and US don't know about troy ounces either; yet it is a unit used in the global precious metal trade even in metric countries (at least in some). As for other elements, see Gold#Price. --Itub (talk) 13:11, 21 September 2008 (UTC)
The only place where the Kg is missing is the table and in that the kg is not very necessary, if we want to be over correct we can make a third column, but for me it is OK.--Stone (talk) 14:39, 21 September 2008 (UTC)
I think there is seriously nothing to expand in the precautions. MSDS's just say "unknown hazards" and give generic recommendations. The quoted book on chemical safety positively says that Ir toxicity has been studied very little. They do mention an experiment in rats inhaling iridium dust, but since it didn't show much toxicity it is not really a reason for "precaution". In fact, I think the section may be too long on the hazards of radioactive iridium. All elements have hazardous radioactive isotopes, and that fact doesn't tell us anything about the element.
I meant add something about being a heavy metal. Nergaal (talk) 09:15, 21 September 2008 (UTC)
There is no evidence that iridium is a "heavy metal" (whatever that means) in the toxicological sense. --Itub (talk) 13:11, 21 September 2008 (UTC)
The heavy metal definition is not good at all. The soluable iridium salts will have a big impact on a human, but nobody ever tested, because you never encounter soluable iridium compounds, except you work in the lab.--Stone (talk) 14:39, 21 September 2008 (UTC)
I think it is still worth mentioning that if falls within the definition of "heavy metal" hazards. Nergaal (talk) 22:14, 21 September 2008 (UTC)
"Western world": those were the words used by the source. It is a bit old, and it was hard to know how much the Russians were producing in those times. ;-) We should update this anyway using the 2008 Platinum report. --Itub (talk) 07:49, 21 September 2008 (UTC)

Compounds paragraph-[edit]

Could this be retitled Chemistry as per the germanium? I have started building some text to add to this here to make the coverage more general- and intend to add it para by para. --Axiosaurus (talk) 16:34, 22 September 2008 (UTC)

Thanks for working on expanding this, that's great! As for the title, I slightly prefer Compounds but I can live with either choice. If we renamed it Chemistry, would we move the part about corrosion resistance (from the first paragraph of the Characteristics section) there? That's also chemistry, I suppose. --Itub (talk) 16:41, 22 September 2008 (UTC)
I'll build the data which relative to the current version would be an expanded list of compounds and little bit more on trend- so perhaps best to wait and see if a title change is warranted.--Axiosaurus (talk) 17:08, 22 September 2008 (UTC)

If, as the article says, "No monohalides or dihalides are known," why is the dichloride listed as the compound where iridium has valence +2?--Syd Henderson (talk) 22:19, 21 June 2009 (UTC)


Should we mention the discovery of the Mößbauer effect in Ir191? It was a Nobel Prize in Physics in 1961.

  • Mössbauer, Rudolf L. (1958). "Gammastrahlung in Ir191". Zeitschrift für Physik A Hadrons and Nuclei (in German). 151: 124–143. doi:10.1007/BF01344210.  --19:04, 22 September 2008 (UTC)
That's a great idea. Maybe under history? I think we still need to expand that section to include the history after the discovery. --Itub (talk) 06:44, 23 September 2008 (UTC)
I've added a paragraph to the scientific applications section. --Itub (talk) 10:50, 25 September 2008 (UTC)
Thanks, will help a liitle when the my fight with the Norovirus is over. --Stone (talk) 21:27, 29 September 2008 (UTC)


several Ir compounds are used as organic light-emitting devices in TVs. someone should add it and find a bunch of refs. Nergaal (talk) 23:58, 22 September 2008 (UTC)

Bits of trivia[edit]

Looking at "what links here" for this article, I came upon these two bits of trivia, which may or may not deserve inclusion in the article but at least I thought I'd mention them here:

1-not sure; 2-seems interesting. Nergaal (talk) 00:56, 24 September 2008 (UTC)


I found a very comprehensive article on the Ir history. I will add more stuff from it but feel free to take a look:

Nergaal (talk) 22:04, 23 September 2008 (UTC)


I added a few refs a while back (Lagowski and Perry), and one of you guys (Itub, Nergaal, Stone?) notes that the status of the ISBNs might be invalid? I went back to the library to double check that I had written them all down correctly, and I had. So what's going on? --Cryptic C62 · Talk 03:22, 24 September 2008 (UTC)

The DOI bot I am using from time to time sees it that way and automatically labels it as such together with all the other edits. You probably should not worry about it. Nergaal (talk) 03:37, 24 September 2008 (UTC)

Red links[edit]

Are all those red links necessary? (Especially those to people's names.) I think red links should only be used when there is reason to believe that an article might be created in the foreseeable future. Not everyone mentioned in passing in a historical article will be notable enough to have an proper article anytime soon (or ever). If someone really wants to create those articles and finds enough information, fine, but why have those annoying red links in the meantime? --Itub (talk) 09:24, 24 September 2008 (UTC)

when I am adding text I automatically links names. I assumed the text would either be changed (possibly dropping the names) or at some point I would go and look for links. You are welcome to unlink them. Nergaal (talk) 16:08, 24 September 2008 (UTC)

A-class review[edit]

I have gone over this article and tried to add more info from my various sources but couldn't find much more to add. There are a few clarify and fact tags, but the article appears to me to be more or less complete content-wise and is adequately cited. The article reads well, is interesting and comprehensive. I therefore would like to know if others agree that this article should be upgraded to A-class. See Wikipedia:Version 1.0 Editorial Team/Assessment/A-Class criteria for criteria. COI - I destubbed this article and have added a minor amount of text in the recent upgrade. --mav (talk) 01:26, 25 September 2008 (UTC)

I don't have any objections, but I hope this will be a short-lived A-class and become FA soon! ;-) (Of course, I may have a COI.) --Itub (talk) 05:09, 25 September 2008 (UTC)
Wow. The first time I visited this article I was disappointed by its lack of information and sources. Great job in upgrading it! Gopher65talk 06:22, 29 September 2008 (UTC)
Done. Normally I'd wait a week but given that plenty of people have seen this message and this article will likely become GA soon anyway, I went ahead and upgraded a bit early. Well done everybody! --mav (talk) 03:22, 1 October 2008 (UTC)

Moved from article[edit]

Now that the article is nearing completion, I think unverified assertions are becoming less tolerable. Therefore I'm moving this paragraph from the applications section here, but if someone can verify it, expand it, and reference, feel free to add it back. In any case I'm not sure if this is one of the more notable applications:

Another use is as selective catalyst for reduction of carbonyl compounds (e.g. unsaturated aldehydes) into unsaturated alcohols, by avoiding the hydrogenation of the alkene double bond.[citation needed]

--Itub (talk) 10:49, 25 September 2008 (UTC)

Oxidation states- and superconductivity[edit]

I have added the −3 oxi state as per Greenwood p1117 to the data table and the element infobox. Greenwood missed -3 in the table on p28. This is not showing in the Ir article on my browser but I think its a cacheing issue.
As a newbie to elements - I am sure the question has been raised before but is there a reason why superconductivity is not in the property list? Iridium is a superconductor and we could use Kittel's element list as the source. --Axiosaurus (talk) 12:11, 25 September 2008 (UTC)

you mean the element infobox? Nergaal (talk) 21:38, 25 September 2008 (UTC)
Yes I do..Sorry should have made that clearer--Axiosaurus (talk) 16:18, 26 September 2008 (UTC)
There was a proposal to expand the {{elementbox}} entrylist on teh wp:elements talk page, but it never really received enough attention. you are welcome to expand it (just announce it somewhere for others to know it). Nergaal (talk) 18:12, 26 September 2008 (UTC)

I didn't know about the superconductivity of iridium, but now that you added it I imagine it's not a very practical one, having a transition temperature way below the boiling point of helium! :) --Itub (talk) 16:16, 2 October 2008 (UTC)

still needed for FAC[edit]

  • use primary units as SI units (at least for total production)?
  • cleanup the isotopes section of the infobox: add 188, 192m→192m2
    • fixed, but I need help with the decay energies
  • mention of sperconductivity
  • anybody known anything of the oxidation -2 for Ir?
  • double check for Another use is as selective catalyst for reduction of carbonyl compounds (e.g. unsaturated aldehydes) into unsaturated alcohols, by avoiding the hydrogenation of the alkene double bond.
  • a picture of "rainbow" salts?

Nergaal (talk) 17:43, 29 September 2008 (UTC)

I take issue with "change all masses to SI units" b/c, as noted above, this metal is traded in the internationally-accepted unit of troy ounces and metric units (Celsius, hour, day for example) are often more useful to readers than pure SI. So anytime troy ounce is used in a source for anything to do with production or demand, it must be used as the primary unit in this article (with the SI conversion in parens). Also, never ever swap units around without noting (at least in hidden comments) what the cited source/reference used. Doing otherwise may corrupt the data if it is swapped back or to a third unit. --mav (talk) 03:18, 1 October 2008 (UTC)

Just to make sure that this is not just an American/UK thing, I searched for news of gold prices (as they are a more popular topic than iridium prices) in Spanish, German, Swiss, French and Italian newspapers. All of them quote the prices in USD per troy ounce. Like I said, I think this is analogous to the standard practice of quoting oil prices in USD per barrel. It is more useful to readers to quote in the same units that are used by nearly every source (with appropriate conversions where necessary). --Itub (talk) 05:57, 1 October 2008 (UTC)
Do you mean SI or simply metric units and US units?--Stone (talk) 22:25, 1 October 2008 (UTC)
I mean give everything in kg or g, and then in parenthesis the whatever else people use. Also, I just saw that EVEN USGS uses metric units for the quantities of platinum metals. Since any self-respecting peer-reviewed organization uses SI's, and even the governmental agency in the US dealing with the survey on production and uses use SI, why do we want to enforce a system that is not even decimal and is standardized in turn to SI? Nergaal (talk) 16:49, 2 October 2008 (UTC)
USGS still uses ounces for the prices, though. And your assertion that any self-respecting peer-reviewed organization uses SI is demonstrably not true. Many fields of chemistry (and science in general) have their own customary units that are not SI and that are used in all peer-reviewed journals. Some examples include kcal/mol, Planck units, atomic units, eV, etc. --Itub (talk) 16:59, 2 October 2008 (UTC)
but not ounces (also, I was referring to lengths; and the atomic units are a special case imo) Ok, so for now switch the production quantities to SI. About the prices, I think the best would be that during the FAC to ask explicitly the reviewers to also put their opinions on the "$/oz" part (sort of like a poll). Nergaal (talk) 18:43, 2 October 2008 (UTC)
If the reference used troy ounces and the topic is production, then we must use the industry standard units as primary and add an SI conversion in parenthesis. I'm all for following international standards but in this case an industry standard (also used internationally) is more appropriate. --mav (talk) 23:19, 2 October 2008 (UTC)

←the reference is a book published in UK. The USGS source gives basically the same number but uses SI units for production (USGS uses only SI's except for the price part). I don't think the choice should prefer a book over a govt source. Nergaal (talk) 00:04, 3 October 2008 (UTC)

The Platinum 2008 report (and the previous years' editions) is the most authoritative source on worldwide PGM production I have found, and is the one cited by other secondary sources such as the technical encyclopedias. The USGS source is not useful for worldwide production because it only lists US imports and exports. --Itub (talk) 05:35, 3 October 2008 (UTC)

I just read the IAEA report about "the bus and the radiography set". I don't think it is worth mentioning it after all, because no one was injured. Some people were exposed to more radiation than they should have, but there were no "deterministic effects" (and about possible long-term "stochastic effects", the report says nothing). This seems to me to be too minor an incident for an article about iridium. I mean, there have been many incidents of small accidental releases of tritium with no known consequences too, but I wouldn't mention them in the article about hydrogen either. --Itub (talk) 09:28, 2 October 2008 (UTC)

  • I've tried to search for examples of Ir(-2) and for free pictures of the colored salts, but haven't been able to find anything. --Itub (talk) 12:57, 6 October 2008 (UTC)

Is this notable enough ? Nergaal (talk) 17:08, 6 October 2008 (UTC)

It is notable enough for kilogram (and in fact already mentioned there), and may be notable enough for silicon, but I don't think it is notable enough for iridium. As the kilogram article shows, there are not one but several proposals for the redefinition of the kilogram; I don't think these proposals belong in the iridium article until one of them gets officially accepted. --Itub (talk) 17:17, 6 October 2008 (UTC)

free image if it is better. Nergaal (talk) 15:36, 7 October 2008 (UTC)

Why the wait?[edit]

Since the goal was to get this article to FAC, I think it was a mistake to list this as a GAN. We now have to wait for the GAN before we submit to FAC. This article has already passed an A-class review and WP Elements regulars know what an element FA needs to be. I suggest we take back the the GAN and submit to FAC. --mav (talk) 02:40, 10 October 2008 (UTC)

I was going to withdraw it a few hours ago but I realized that the decay energies in the infobox are still missing. I went ahead and nominated it. Conominators please drop your signature there. Nergaal (talk) 02:55, 10 October 2008 (UTC)


Hi team. Wow, another awesome effort from those that have or make time :) Some minor changes made, and some notes and also suggestions where I don't think it's clear-cut enough for me to make a change:

  • Siderophilic is linked to siderophile as this page explains what it means, and then offers the link to the chemistry-related page.
  • The chembox picture isn't that clear, but will be fine in lieu of no better choice
  • I seem to remember that units needed to be written in full (on first use) and then abbreviated e.g. millisecond (ms), and then abbreviated from then on? Not sure on that one.
  • The Crabtree and Vaska diagrams are at odds stylistically, mostly because they are so close together and the drawings are not to the same scale. Moving them apart would be an easy fix but changing one of them would be nicer (and then of course, the actual diagrams are different sizes which creates another style issue...).
  • I seem to remember that any link must avoid a redirect, I've changed as many as I've found. Unsure of whether this is a GA requirement.
  • I'm assuming the red links will be taken care of? I've left them for now.
  • The colour inconsistency still seems there (see above by Itub)

Best of luck Freestyle-69 (talk) 05:46, 8 October 2008 (UTC)

Thanks. I have never heard about links having to avoid redirects, is that a rule written somewhere? I would disagree with such a rule, as I intentionally link to redirects on many occasions when it is clearer! --Itub (talk) 07:35, 8 October 2008 (UTC)
I looked at the guidelines and in fact they say Do not "fix" links to redirects that are not broken. But don't worry, the changes you made certainly don't hurt--it's just something we need not worry about. --Itub (talk) 09:08, 8 October 2008 (UTC)
Err, woops, me and my creative memory... :) I do see the sense in that now. Cheers, Freestyle-69 (talk) 21:18, 8 October 2008 (UTC)
Well... there is no *real* need to avoid redirects (disambiguation pages yes, but not redirects). But. As a very minor style issue, instead of using [[molars]], use [[Molar (tooth)|molars]] instead. "molars" redirects to "Molar (tooth)", so it is no big deal, but the latter method avoids a redirect while looking and reading the same in the final copy. Every time you use an unnecessary redirect you are making the servers work twice as hard as they need to (but it's a very minor thing none-the-less). Gopher65talk 21:17, 9 October 2008 (UTC)

Iridium in Jewelry[edit]

Can Iridium be used in jewelry or is it too difficult to work? (talk) 20:39, 29 October 2008 (UTC)

If you ask the right person you get a pure iridium ring , this is not impossible, but for normal jewlery platinum or mixtures of platinum and the other platinum group metals are prefered. The gold smith round the corner will be not able to fullfill the task.--Stone (talk) 23:04, 29 October 2008 (UTC)


Excuse my ignorance, but how might one delete vandalism which appears in an article but is not there when one attempts to edit? I can't seem to find or delete this:

also the word *Bromo* means same sex male friends that will one day have intense passion with one another in the form of a threesome also called a *SquizManMitch*

...and yet it remains on the page. I'd love to know how to deal with this in future, if possible. —Preceding unsigned comment added by Misha Vargas (talkcontribs) 19:37, 11 February 2009 (UTC)

Oh, I think I see what's been done. It's the infobox, isn't it?. And, by a quick check... it's affecting other element pages, like osmium, platinum and gold.
Misha Vargas (talk) 20:12, 11 February 2009 (UTC)

Ambiguous sentence in lead:[edit]

"It is thought that due to the high density and siderophilic ("iron-loving") character of iridium, most of the iridium on Earth is found in the inner core of the planet. " In which direction does the speculation run in this statement? Is it that iridium has been found in the core in huge amounts, and they speculate that it's a result of the siderophilic character, because the core has lots of iron, or is it that they know iridium is siderophilic, and they know of a huge iron core in Earth, thus they predict the iridium presence. ThuranX (talk) 00:34, 21 June 2009 (UTC)

I tweaked that sentence hoping its clear now. Materialscientist (talk) 00:44, 21 June 2009 (UTC)

And vice versa?[edit]

"The [IrCl6]2− ion has an intense dark brown color, and can be readily reduced to the lighter-colored [IrCl6]3− and vice versa."

Surely that doesn't make sense? If A can be reduced to B, then "and vice versa" would imply that B can be reduced to A. Kay Dekker (talk) 01:45, 21 June 2009 (UTC)


"with an average mass fraction of 0.001 ppm in crustal rock, it is 4 times less abundant than gold, 10 times less abundant than platinum," indicates platinum is more abundant than gold in the crust. Am I interpreting this correctly? And if so, isn't that an error? --Preston McConkie (talkcontribs) 05:39, 21 June 2009 (UTC)

Some sources may differ because there is some uncertainty about the abundance of the rarest elements, but you are reading it correctly. Platinum is more abundant than gold, at least according to the source cited. Remember that this is average abundance, but what matters for practical extraction is not so much the average but the availability of relatively rich sources. --Itub (talk) 17:02, 21 June 2009 (UTC)
PS: see also the same question above at Talk:Iridium#Occurrence. --Itub (talk) 17:05, 21 June 2009 (UTC)

Most stable isotopes includes non-stable isotopes[edit]

Why does the list of "most stable isotopes" in the huge data box list radioactive isotopes? I don't think they qualify for "most stable" by any stretch. 192Iridium is one of the two most common gamma ray sources (along with 60Cobalt) produced from 191Ir in nuclear reactors. It's a major and important application, its use as an industrial gamma ray sources, that is completely omitted from this article, and I would like the information added, but I'm stymied by the article listing radioactive isotopes as stable isotopes--it makes the accurate addition of correct information a sudden source of contradiction and confusion. 192Ir is not a stable isotope and should not be listed as one. -- (talk) 06:29, 21 June 2009 (UTC)

I don't see a contradiction. "Most stable" compares stability of different isotopes of Ir, it does not mean "stable". In this sense, 192Ir does qualify. I guess the list is long simply because someone had patience for typing :) Thank you for note and you are more than welcome to add application of 192Ir into the main article, supported by references. Regards Materialscientist (talk) 07:07, 21 June 2009 (UTC)
"Stable" when discussing isotopes already means non-radioactive (stable isotope). Your comment that more stable compares stability but does not mean stable does not make sense. Is this a joke? "Stable" means stable.-- (talk) 08:29, 21 June 2009 (UTC)
  • “Natural iridium contains two stable isotopes.” [1]
  • “Firstly, iridium has two stable isotopes: iridium-191 … and iridium-193…” [2]
  • “Iridium has two stable isotopes, 191 and 193, …” [3]
  • “We could use an iridium foil because iridium only has two stable isotopes 191 (37.3%) and 193 (72.7%).[4]
  1. ^ Lide (editor), David R. (1995). Handbook of Chemistry and Physics. CRC Press. p. 4-16.  Unknown parameter |isbn-13= ignored (help)
  2. ^ Podgorsak, Ervin B. (2005). Radiation Physics for Medical Physicists. Springer-Verlag. p. 302.  Unknown parameter |isbn-13= ignored (help)
  3. ^ Lusi W. Alvarex and W. Peter Trower (editor) (1987). Discovering Alvarez: Selected Works of Luis W. Alvarez with Commentary by His Students and Colleagues. University of Chicago Press. p. 252.  Unknown parameter |isbn-13= ignored (help)
  4. ^ Walter D. Loveland, David J. Morrissey, Glenn Theodore Seaborg (2005). Modern Nuclear Chemistry. Wiley. p. 242.  Unknown parameter |isbn-13= ignored (help)

No joking. Isotope X being more stable than Y does not mean X is stable on its own. Materialscientist (talk) 08:33, 21 June 2009 (UTC)

Well I learn something new. How about a scientific reference that discusses radioactive isotopes in terms of relative stability rather than in terms of half life so I can see it in use? I'm looking for one on Iridium in particular, but cannot find anything on-line or on-shelf. Probably you have better sources available. I think it is confusing to the average reader of a general encyclopedia to be told there are only two stable isotopes (linked) in the first paragraph and then get a list of "most stable" isotopes that includes more than two in an information box. A reference will help me rewrite this part so that the average user is not left out in the cold from knowledge. -- (talk) 08:45, 21 June 2009 (UTC)

1. The article already mentions the use of Ir-192 as a gamma-ray source and has for a long time. 2. I don't see anything wrong with saying than one isotope is more stable than another, despite both being unstable. For example, Ir-192 is more stable than Ir-177. --Itub (talk) 17:08, 21 June 2009 (UTC)
I also "don't see anything wrong with saying than one isotope is more stable than another, despite both being unstable." But that's not what you've done. You've included stable and unstable isotopes and called them "Most-stable isotopes." Ir-191, and Ir-193 are both stable isotopes. Ir-192 is a radioactive isotope. The terminology is so confusing your defense of it misses its target. Probably my question of it missed the target, also, as the problem is including the stable isotopes. But the chart is so confusing it is hard to tell what is being attempted with it. There's no point in including this misinformation in the information box on elements. -- (talk) 21:44, 21 June 2009 (UTC)
If you want to see plenty of examples of published comparisons of stability of radioactive isotopes, see [1] and [2]. --Itub (talk) 17:19, 21 June 2009 (UTC)
Thanks for taking the time, see comment below. -- (talk) 21:45, 21 June 2009 (UTC)

Oxidation states and other matters[edit]

It is inconceivable that Ir does not form any complexes with oxidation state -2, though none are mentioned in G&E and I can't give a specific example at the moment. If I get the opportunity I'll look it up in "Comprehensive Inorganic Chemistry". With transition metals there is no good reason for the "non-existence" of intermediate oxidation states. In the case of Ir, cluster formation makes everything possible.

As some of the contributors to this article will know I find the quality of the inorganic and organometallic chemistry to be very poor in many of the "element" articles. This one is no exception. The problem seems to originate with the use of Wiberg as a principal source. Simply cataloguing some of the compounds formed is a very old-fashioned approach. Why no mention of the fact that Ir is in the Co group. Why is electronic configuration only mentioned in the last paragraph? Why no comparative chemistry with, say, Rh or Pt? Why no mention of aqueous solution chemistry? My point is that in the absence of context the catalogue of compounds is no more informative than a menu in a restaurant.

My re-writing of Compounds of zinc shows how I think the chemistry of an element should be treated. Sadly I don't have the time to do the same job with all the other elements that need it doing. Petergans (talk) 08:39, 21 June 2009 (UTC)

But I'd at least use "most stable" here, when discussing oxidation states. Yes, the article is strangely not an article, but a list without prose. -- (talk) 08:47, 21 June 2009 (UTC)

I've reshuffled the sections. I'm not chemist to argue with you on oxidation states, but will just throw two observations of mine: (i) sometimes a compound not observed means simply nobody cared to try to make it; (ii) similar elements do no mean same chemistry - lanthanides are different, e.g. their energies of 4+ and 2+ states differ a lot. Same for noble metals - oxidation is very different. Thus I would stick to (i) and still use stable compounds as an indicator. As to criticism, IMHO WP is lacking scientists who can rewrite, thus if you want a thing well done, do it yourself. Materialscientist (talk) 08:57, 21 June 2009 (UTC)

Replying to Peter's questions. I agree that the coverage of inorganic and organometallic chemistry in this article is somewhat cursory. Having something similar to your excellent article on the compounds of zinc would be great, although I think it would be too much detail for this article and would have to be replaced with a summary and a link to a more detailed compounds of iridium. One problem we faced is that there is a certain lack of information specifically about the chemistry of iridium in the sources that we consulted. I didn't look at Wiberg, but Greenwood puts iridium in the cobalt chapter, where cobalt gets most of the attention. I also looked at the industrial chemistry encyclopedias, but there it is lumped with the platinum group metals where platinum gets most of the attention. Same with many articles from the platinum metals review. I hope Comprehensive Inorganic Chemistry will do better, so please let us know if you find something useful there. But overall I agree that some discussion of the electronic configuration and a comparison between Ir and other elements would be a worthwhile addition.
Regarding oxidation states, the "unwritten policy" as I see it has been to only include oxidation states for which there are documented examples. Otherwise we are just speculating. While I agree that there should not be a fundamental reason why Ir(-2) should be impossible, it is at least conceivable that no one has bothered publishing about it. Certainly no one has found such a publication and cited it from this article yet. So I think we have to remove all mention about oxidation state -2 until we find such a publication. --Itub (talk) 12:42, 22 June 2009 (UTC)
G&E mention electrochemical evidence for Ir(2-) in relation to bipy complexes. Petergans (talk) 21:00, 22 June 2009 (UTC)
I don't think that's quite enough; apparently it wasn't enough to convince G&E themselves to add it to their own table of oxidation states. Of course one can usually find electrochemical evidence for intermediate oxidation states, but tables of oxidation states, as well as claims of "X forms a compound in Y oxidation state" generally focus on compounds that have been isolated (although in some cases in farily exotic conditions). I don't object to adding that Ir(2-) has been observed electrochemically, but saying that it forms compounds would require a better example in my opinion. --Itub (talk) 11:32, 23 June 2009 (UTC)
Hmm, if there is electrochemical evidence it's only a matter of finding the right conditions to prepare a solid compound. The implication that no compounds have been made or published is unwarranted unless a thorough literature search has been made. After all, G&E is now more than 10 years old and CIC is even older. Petergans (talk) 14:57, 23 June 2009 (UTC)
True, like they say, "one can't prove a negative". I'm not suggesting we say flat out that there are no Ir(2-) compounds, just that we should be silent about it until we have an example. I wouldn't feel right about the opposite implication that "we are sure someone must have made one but we don't know what it is". At this point I'd be happy with just removing the word "all" and say "Iridium forms compounds in oxidation states between −3 to +6". --Itub (talk) 13:12, 24 June 2009 (UTC)

Agreed and done. Petergans (talk) 14:51, 24 June 2009 (UTC)

Badly worded statement[edit]

"Iridium has been linked with the extinction of the dinosaurs and many other species 65 million years ago.". No! Iridium has not been linked to the extinction of the non-avian dinosaurs. Vastly increased iridium content at K/T was the evidence that first suggested an impact of an asteroid or comet. The impact (and its aftereffects) are what has been "linked" to the K/T mass extinction, not the iridium. (talk) 15:32, 21 June 2009 (UTC)

Being "linked" does not mean being a cause. It just means that there is a correlation. --Itub (talk) 17:10, 21 June 2009 (UTC)
This is supposed to be a general encyclopedia. The other IP is correct, Iridium is linked with meteors, and also with the K/T boundary, not with the extinction of the dinosaurs. A logical extension beyond the scope of the actual research.
This is not a good article. It has problems, number one is internal inconsistency about its intended audience. Are you using "linked" for "correlation" for a statistician or for a general audience. If the first, your target is wrong, if the second your usage is wrong. But, again, either way, the IP stands correct.
Your links about on "most stable isotope" use the term with elements Francium, Uut, Rg, Uuq, Polonium, Plutonium and the like. But the books all define and use "stable isotope" in the same way: an definition that is easy to use with consistency for a non-technical audience. The table should not include a messed up mix of stable and unstable, naturally occurring and artificial radioactive isotopes. The jumble confuses rather than presents anything succinctly for the reading audience, plus, the unexplained changed of nomenclature makes it useless. It would be simple and useful to include stable isotopes, followed by naturally occurring unstable isotopes, followed by man-made radioactive isotopes, listing only those with significant half-lives in order of half-life.
There is one exception in the links you provided to the use of "most stable isotope" among radioactive isotopes, Earth: Evolution of a Habitable World by Jonathan I. Lunine, Cynthia J. Lunine (Illustrator) uses the phrase to call Helium-4 "the most stable isotope of Helium" on p. 36.
I'm not going to look through more of the sources, although I appreciate you took time to try to address my question rather than ignoring it.
This article is a mess of misinformation for an uncertain audience. I've been told if I want better I can rewrite it, but the authors seem not to want a clear-cut article for a general reader. -- (talk) 21:36, 21 June 2009 (UTC)
What was the question again? --Itub (talk) 22:55, 21 June 2009 (UTC)
It's not a question, it's a comment about a problem with the article. It should not state iridium "has been linked with the extinction of the dinosaurs." That's incorrect. It's the meteor that gave rise to the iridium in the layer that is linked with the extinction of the dinosaurs.
In addition are comments about the problem with the information box labeling isotopes as "most stable isotopes."
These are posted together because they are a couple of examples of the article being loose while using terminology and not accurately getting the science from the references, in addition to assigning different meanings to the same term as is convenient, and, in general, not properly identifying the audience. It's hard to be too clear when the article itself is all over the place. -- (talk) 23:02, 21 June 2009 (UTC)
OK, I'll try to address the question that is not a question. I have to agree that "linked" could use a clearer alternative to avoid misunderstandings (just look at what happens whenever X is linked to cancer or Y is linked to crime). However, I'm not convinced that the long and convoluted sentence that resulted from your editing is an improvement because by the time the readers get to the end they will have forgotten that the sentence that ends with talk about extraterrestrial objects indeed began discussing something about iridium just like this long and convoluted sentence began discussing something about sentence length without even using a comma!
Can we discuss the article? Could you have devoted those 20 seconds to rewriting the sentence instead?
This is a discussion page. It is not a question and answer page. Editors discuss issues in articles all of the time without raising every point of discussion as a specific question. It's called "discussion." Once you've decided you are discussing the article, then focusing on another editor's method of raising issues is not conducive to a useful discussion.
Second, a story. The list of isotopes used in the infobox used to be called "selected isotopes", until some other member of the bike shed color selection committee came along. The complaints at the time were that the selection criteria were not explicit and that how dare we imply that we "selected" something! (This would go against someone's dream of having editors who are unthinking robots that only transcribe sources.) Anyway, there was in fact a selection criterion, and it was to list the longest-lived isotopes, which of course includes the stable isotopes with their "infinite" lifetime. Someone changed it to "most-stable isotopes" and everyone was happy. Now, if you can't digest the idea that the word stable can be used in both an absolute and a relative sense, we could perhaps change the heading of the table to "longest-lived isotopes". Would that be work for you? --Itub (talk) 12:22, 22 June 2009 (UTC)
It would not be much code to include stable isotopes first, listed as "stable isotopes," then "longest-lived isotopes." It would be accurate. It would be easy to explain to the general audience. It would be easy to incorporate the information into the text in a manner that makes the information box even more useful. I think this would work well for a lot of readers using the information box to get information. -- (talk) 17:16, 22 June 2009 (UTC)
I recommend taking that suggestion to WP:ELEMENTS, because it would represent a change to the template that affects every element article. --Itub (talk) 11:25, 23 June 2009 (UTC)

Comments on inorganic chem[edit]

I was going to redraw the C-H activation scheme (organometallic chemists would have a fit about hint of planar IrIIIL6). The article implies that luminescent Ir complexes are used in some sort of displays: "One of the major uses for this family of complexes have been the flat panel displays that are found in televisions or monitors.[60][61].", but this app is probably not real. Just some academics talking about how something could be used. Also one of the refs is to the journal of undergrad rsch?? Is that useful? The only application I can find for Ir compounds is the Cativa process, as already described. Lots of reactions have been developed in asymmetric catalysis, and possibly some have been commercialized in certain fine chemicals syntheses. I'm looking for others.--Smokefoot (talk) 23:12, 23 June 2009 (UTC)

You may be correct about the displays; that's one item I never had the time to verify and I don't remember who added it. Feel free to improve the schemes; I'm extremely lazy when it comes to producing such figures, so in some cases I just reused what I found in other articles even if suboptimal. --Itub (talk) 13:08, 24 June 2009 (UTC)

Flammable vs Inflammable[edit]

The term "inflammable" is highly confusing as in many places it would mean "non-flammable", see . On the other hand, "flammable" is blatantly obvious. I have changed it to "flammable" to prevent this confusion. (talk) 08:31, 8 August 2009 (UTC)

Iridium is denser than osmium[edit] (talk) 23:41, 14 March 2010 (UTC) —Preceding unsigned comment added by (talk) 23:18, 14 March 2010 (UTC)

The front page will all the elements give other numbers than the page of the elements itself, this makes this page incredible credible and therefore all numbers on that page are simply not credible.--Stone (talk) 15:03, 28 March 2010 (UTC)
Even though the pages of the elements show different densities than the front page, the densities of of Ir an Os on the front page is correct. Os and Ir has a density of 22.61 g/cm3 and 22.65 g/cm3 respectively. (Source: Shriver and Atkins, Inorganic Chemistry fifth edition (2010) (p. 453)) and thus Ir is the most densest metal. (Yfé (talk) 16:40, 30 May 2010 (UTC))
Go and read the sources cited in this article. Textbooks generally don't provide sources for data and are often outdated or wrong. This article directly cites what IMHO is the most recent and accurate measurement for the densities of Ir and Os. --Itub (talk) 01:43, 7 August 2010 (UTC)
The source I gave was from 2010, and the one in the article is from 1989, and the plausibility that that article was outdated was quite large in my opinion. I have now bought another book which states the same thing as the source article, but this source is twenty years younger, and is thus (in my opinion) in the same line of credibility as Atkins' book.Yfé 17:33, 29 September 2010 (UTC) —Preceding unsigned comment added by Yfé (talkcontribs)

General Properties Error - Inconsistent Electrons per Shell[edit]

There appears to be an error in the box on the right, labelled "General properties." In the section describing the number of "Electrons per shell," the box reads: 2, 8, 18, 32, 15, 2 (Image) But when the image is viewed, it depicts: 2, 8, 18, 32, 17

Can iridium have 5 and 6 electron shells? Christopher, Salem, OR (talk) 07:17, 27 July 2010 (UTC)

Yes check.svg Done 2, 8, 18, 32, 17 is incorrect. The image has been changed to 2, 8, 18, 32, 15, 2. Double sharp (talk) 13:13, 25 March 2012 (UTC)


Why is the main article semi-protected? Pyotrveep (talk) 02:11, 11 May 2013 (UTC)

Because a user has been abusing multiple accounts in an attempt to add trivia to the article. —C.Fred (talk) 02:14, 11 May 2013 (UTC)
What were the edits talking about? I'm suspecting a disconnection on what is thought of as important. — Preceding unsigned comment added by Pyotrveep (talkcontribs) 02:17, 11 May 2013 (UTC)

Failed verification and apparently incorrect derivation of name[edit]

The source that says Tennant named this after the Greek Goddess Iris fails verification, and Tennant's original notes indicate no such exact derivation. Specifically, Weeks' Discovery of the Elements' says Tennant "named it IrIdium because it salts are of varied colour", and that's from page 437; page 418, as cited, mentions nothing about the coining and certainly nothing about him naming it after the Greek goddess specifically (you can view the text in its entirety here). So, unless another source actually says this, what it should say is some version of that the Latin root "ir" means many-colored and Tennant used that root to form the name because of the coloring he observed in Iridium salts. Of course, the Greek Goddess' name is from the same derivation, but the article explicitly states that Tennant named it after the goddess, citing this source, when as far as I can tell from the sources I've looked at, we have no idea if Tennant even knew of the goddess. We only know he knew the meaning of the language root. A footnote can also be placed showing what he actually wrote in his notes, held by London's Royal Society: "I should inclined [sic] to call this metal iridium from the striking variety of colours which it gives while dissolving in [illegible] acid" (as read by Martyn Poliakoff here, starting at 2:34 in).--Fuhghettaboutit (talk) 01:57, 13 February 2015 (UTC)

Iridium Rocket Fuel[edit]

Thrusters on spacecraft use Hydrazine decomposition catalyzed by Iridium (usually, also Ruthenium)metal. See article at and Aerojet/Rocketdyne. 2001:4898:80E0:EE43:0:0:0:2 (talk) 08:17, 11 June 2015 (UTC)

Iridium-titanium alloys for deep sea piping ???[edit]

The article states "Certain long-life aircraft engine parts are made of an iridium alloy, and an iridium–titanium alloy is used for deep-water pipes because of its corrosion resistance". I can only find evidence for the first part in regard to spark plugs, and I can't find evidence for the second part at all. I'm inclined to remove the sentence (which I notice has propagated over much of the Web as sentences from wikipedia articles are prone to). Fivemack (talk) 13:26, 16 October 2015 (UTC)

External links modified[edit]

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Image description confusing[edit]

The main image of the element has the subtitle: "Two square pieces of gray foil", although the image is clearly not gray foil, but rather nuggets of some sort. Douira100 (talk) 17:42, 13 October 2016 (UTC)

I have updated the image caption to read "Pieces of pure iridium". Thanks for catching the error and reporting it here. -- Ed (Edgar181) 17:49, 13 October 2016 (UTC)