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WikiProject Elements (Rated Bplus-class, High-importance)
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Article changed over to Wikipedia:WikiProject Elements format by User:maveric149. Elementbox converted 10:10, 15 July 2005 by Femto (previous revision was that of 18:51, 10 July 2005).

Information Sources[edit]

Some of the text in this entry was rewritten from Los Alamos National Laboratory - Radium. Additional text was taken directly from (input radium into search field) and USGS Periodic Table - Radium. Other information was obtained from the sources listed on the main page but was reformatted and converted into SI units.


I'm a bit puzzled by the description "Transuranic is (SIC) character". It's not actually transuranic, as everyone who follows this link will know.

Can whatever this means be expressed more clearly, I wonder.Andrewa 18:18 Mar 5, 2003 (UTC)

The source of this error appears to be the online elements database which has now been corrected. I have deleted the reference to transuranics on this page. It's still not very elegant prose. Andrewa 05:55 Mar 10, 2003 (UTC)


Here it says : On February 4, 1936 Radium E became the first radioactive element to be made synthetically. On the Technetium page, it says: Technetium was the first element to be artificially produced. (in 1937) One of these statements must be false. Malbi 11:20, 2 Feb 2004 (UTC)

They are one and the same. It was called Radium-E for want of another name, as it resulted from experimentation on radium. Later, when it was isolated and described, it got a formal new name. SkoreKeep (talk) 02:29, 17 February 2014 (UTC)

Eh? Radium E is 210Bi, not Tc. I suspect the sentence meant to say "first radioactive isotope" (or perhaps nuclide) rather than element. Double sharp (talk) 07:10, 9 September 2014 (UTC)

Red spectrum or green[edit]

In the History section, it seems to imply that Barium has a Red spectrum, in fact Sr is Red and Barium is Green :) 13:08, 6 December 2006 (UTC)YT2095

Marie Curie's death[edit]

About the phrase in the article: Handling of radium has since been blamed for Marie Curie's premature death.

I have just read that Marie Curie lived 67 years (1867 – 1934), so that is not such a premature death. Well, she died of leukemia, so my question is: At which point did her death generate a global warning about radiation?


a response

"Premature death" is when death occurs earlier than it would have otherwise. a person who died in a car accident at age 120 would still be a "premature death."

Curie died of leukemia and it could've been caused by exposure to radium or other radio active elements, so such speculation, although not fruitful, would still be rationally justified.

She may have lived another twenty-five years or more, but that's also speculative. — Preceding unsigned comment added by (talk) 02:58, 9 February 2014 (UTC) (talk) 02:59, 9 February 2014 (UTC) Michael Christian

"Premature death is when death occurs earlier than it would have otherwise." - This is just silly. — Preceding unsigned comment added by (talk) 19:25, 15 April 2014 (UTC)

Chemical Properties[edit]

What is meant by the comment about the discoloration of radium on exposure to air: "probably" due to nitride formation? Is this an aspect of the chemistry of Ra that has never been investigated? I think the comment should be clarified or removed. Hmoulding 20:47, 9 August 2006 (UTC)

Oxidises or nitrides?[edit]

This article contradicts itself. At the top it says that radium blackens in air by oxidation. Lower down it says that it blackens probably (sic) by nitride formation. Macboff 22:14, 19 January 2007 (UTC)

That may not be a contradiction. Oxidation is governed by electron loss, and needn't (I think, IANAChemist) actually involve oxygen. 15:53, 29 October 2007 (UTC)


Does radium actually glow green, or is that just a myth? —Preceding unsigned comment added by (talk) 17:38, 28 January 2008 (UTC) Bold textMyth; it glows blue76.174.27.179 (talk) 03:45, 9 September 2013 (UTC)


"Radium was added to food for taste" What does it taste like? (I'm assuming it was in the form of some salt, perhaps like RaCl2) —Preceding unsigned comment added by Jaded-view (talkcontribs) 04:04, 4 February 2008 (UTC)


This quote.

Although tritium's beta radiation is potentially dangerous if ingested, it has replaced radium in these applications.

I think it deserves mention that Tritium has a shorter half-life and does not bioaccumulate like Radium does. Is this correct? —Preceding unsigned comment added by (talk) 20:13, 22 September 2008 (UTC)

How can beta radiation be ingested? (talk) 08:52, 30 March 2011 (UTC)
Small particles emitting beta radiation (dust) can be flying around and ingested. Materialscientist (talk) 09:11, 30 March 2011 (UTC)
I changed the sentence so that it says that tritium is ingested, not beta radiation, and that tritium, not beta radiation replaced radium.Wikimedes (talk) 18:41, 20 June 2011 (UTC)

Which ispotope[edit]

Which isotope exhibits the radioluminescence of radium? Which was used on the watch dials?-- (talk) 13:04, 15 May 2009 (UTC)

It's not the radium that glows. It is mixed with activated zinc sulphide, which glows when bombarded with alpha particles. So all of the isotopes and decay products that alpha decay are contributing to the glow. DonPMitchell (talk) 03:35, 13 August 2010 (UTC)

true — Preceding unsigned comment added by (talk) 04:25, 9 September 2013 (UTC)

As to which one would activate ZnS, all of them; in fact the shorter half-life isotopes would no so even more efficiently, though the effect would fade quickly, even if those isotopes could be generated in enough quantity. In fact, any alpha emitter would work; the question is the tradeoff between brightness per quantity used vs speed of decay. Stupid ispotopes. SkoreKeep (talk) 02:41, 17 February 2014 (UTC)

Discrepancy with source[edit]

According to the Los Alamos National Laboratory, 1 ton of pitchblende yields 1/7 of a gram of radium, whereas the article states in "Occurences" that a metric ton (a larger amount) yields only .0001 grams of radium. I am updating the article with this information; if it is incorrect, please revert.NotALizard (talk) 21:34, 5 August 2009 (UTC)

I think you're absolutely right, thanks! The article did say 1 gram per 7 tons originally, but it was changed by an anonymous edit in November 2006, without any source or explanation. It's a bit embarrassing that this wasn't caught until now. Hqb (talk) 08:03, 6 August 2009 (UTC)

Hotel Radium Photo[edit]

Hi Materialscientist - you're right in a sense, the hotel was using the popularity of Radium at the start of the 20th century, as were the toothpaste etc. that is mentioned in the article. I just put the photo there as an illustration of this popularity. The hotel is long since 'dead' and so is the popularity of Radium as a consumer product! However - if you own this article then so be it... — Preceding unsigned comment added by Deasington (talkcontribs) 08:42, 10 August 2011 (UTC)

Nobody owns articles here. This might be an interesting short addition (on the use of radium for business promotion), but if properly described and referenced. Materialscientist (talk) 08:49, 10 August 2011 (UTC)


--Stone (talk) 21:19, 20 June 2012 (UTC)

Let's move this where it will do more good[edit]

This sentence:

The SI unit of radioactivity is the becquerel (Bq), equal to one disintegration per second. The curie is a non-SI unit defined as that amount of radioactive material that has the same disintegration rate as 1 gram of radium-226 (3.7×1010 disintegrations per second, or 37 GBq).[8]

is a nice bit of information that should be on Wikipedia somewhere, but it has no purpose here. Let's move it somewhere where it will do more goo. Poihths (talk) 13:33, 28 January 2013 (UTC)

IMHO it is relevant here because the definition of the curie specifically refers to radium-226 (the commonest radium isotope). But I would prefer placing the curie before the becquerel here as the becquerel has nothing to do with radium:
"The curie is a non-SI unit defined as that amount of radioactive material that has the same disintegration rate as 1 gram of radium-226 (3.7×1010 disintegrations per second, or 37 GBq). The SI unit of radioactivity is the becquerel (Bq), equal to one disintegration per second."
Double sharp (talk) 15:10, 28 January 2013 (UTC)
One can find out all about the curie and the becquerel by simply linking to the respective articles. That's the point of having the internal links, like the one to curie in the History section of the article, where the connection between the unit and the scientist is appropriate. SkoreKeep (talk) 02:19, 17 February 2014 (UTC)

Cobalt and cesium are not substitutes for radium[edit]

Cobalt and cesium are not substitutes for radium. They are gamma emitters; radium is an alpha emitter. Gamma emitters are not used to make luminescent paints. Both of these gamma emitters are more dangerous to handle and work with than radium is. Mention of these two "substitutes" should be deleted from the article. Rwflammang (talk) 13:32, 17 June 2013 (UTC)

Radium was for a long time the only possible radio isotope at all. It was used for radiation therapy and other applications were gamma and beta emitters would be the better choice, but after cobalt and caesium isotopes were available radium fell out of use. Why is there no radium used anywhere anymore, when it is less dangerous? --Stone (talk) 20:52, 17 June 2013 (UTC)
They are substitutes in a medical sense, where the technical differences are known and respected. They today treat the same problems radium did in the past. SkoreKeep (talk) 02:20, 17 February 2014 (UTC)

"Recreational use" section seems misnamed[edit]

the "Recreational use" section is misnamed, since it focuses entirely on quack uses of radium. Quackery is not a type of recreation. — Preceding unsigned comment added by (talk) 02:52, 9 February 2014 (UTC)

Agree. let's go with "Commercial use". Change made. SkoreKeep (talk) 02:36, 17 February 2014 (UTC)

Isolation of pure radium chloride[edit]

The article somehow omits the work undertaken by the Curie's during almost four years from radium detection (1898) to the isolation of 100 miligramms of pure radium chloride in 1902, a process during which they had to make some 45000 fractional crystallizations, with their own hands. None, before or after, has devoted such amount of time and energy in the isolation of a chemical element.

References: — Preceding unsigned comment added by (talkcontribs)

This is covered at Marie_Curie#New_elements, which is linked from this article. VQuakr (talk) 20:58, 5 May 2014 (UTC)

GA Review[edit]

This review is transcluded from Talk:Radium/GA1. The edit link for this section can be used to add comments to the review.

Reviewer: Protonk (talk · contribs) 14:27, 4 October 2014 (UTC)

By and large this article is pretty good. I recognize that Radium is a bigger challenge to tackle than some of the other elements you've done because of the unique and unfortunate (for our purposes) coincidence of its historical significance and lack of modern research. That said, the article does a good job laying out the physical/chemical/nuclear properties of radium and giving context to those properties--i.e. by the time we get to the discovery section we're equipped to understand how the Curies extracted radium and why it might be found in uranium. That's good and not something you see all the time in articles which mix science and science history.

Thank you! I consciously aimed for that. Yes, it is really unfortunate – it means we have to be somewhat equivocal about the precise properties of Ra, because there haven't been modern experiments to accurately pin them down, and there are multiple conflicting values from the early 20th century. Double sharp (talk) 14:45, 4 October 2014 (UTC)

I will say that I think the historical uses and sections on the development and production of radium could be expanded. Some of my suggestions I've left below as specific notes but there is a surfeit of sourcing (lol) on the production and applications of radium from ~1900-1960. It would be a shame to promote this article without a more comprehensive (or at least better sourced) look at those areas, given that they're one of the reasons radium is as important as it is. I'm happy to do some gophering for sources (especially those on JSTOR, as I have access to that but no access to a university library) if need be and I'm also open to being convinced that this demand is unreasonable for a GA, but I don't think it will be too hard to overcome.


  • This is up to your discretion (as I'm sure there's a MOS note on where to link that I haven't read), but we link Primordial nuclide in "primordial thorium". It might be better to forego that link for a sentence and link to it when we spell out "primordial radionuclides"
  • "...them is radium-205m, with a half-life of between 130 and 230 milliseconds. All ground states of isotopes from..." I'd say remove the milliseconds wikilink and link ground state
  • "It is 2.7 million times more radioactive than the same molar amount of natural uranium..." Probably don't need to link "uranium" here as we linked to 235 and 238 (the latter twice) in the section.
    • Well, natural uranium is a mix of 238U, 235U, and traces of 234U, so that while the main point is certainly 238U, the faster decay rate of the other two natural U isotopes should be significant enough that it might misrepresent the source a little to not accentuate that it means natural U. Also, thanks for noting the doubly linked 238U: cut the second one. Double sharp (talk) 13:31, 8 October 2014 (UTC)
      • Got it, Yes check.svg Done Protonk (talk) 15:25, 8 October 2014 (UTC)
  • this should be converted from a bare link to a citation template


  • "Today, the latter usage is no longer in vogue..." While technically correct (I think), we've got three uses here: nuclear medicine, radioluminescent devices and quakery, so "latter usage" could refer to the last two or just the middle one (or the last, I guess, but that's not the indication I get from the text).
    • Changed to "Today, these former applications are no longer in vogue..."; better? Yes, I meant the last two. Double sharp (talk) 13:26, 8 October 2014 (UTC)
      • It's still kinda unclear. This may make the text a bit more bloodless, but would it make sense to say "it's now only used for nuclear medicine" or something like that? I dunno, this is a small issue. Let's call it good for now and worry about the other stuff. Protonk (talk) 15:24, 8 October 2014 (UTC)
  • "At standard temperature and pressure, radium crystallizes in the body-centered cubic structure, like barium..." How about "Like Barium, At standard temperature and pressure, radium crystallizes in the body-centered cubic structure"? That's maybe a bit fiddly but it avoids my having to wonder whether the crystalization is like barium or the bond distance is like barium
  • When talking about the chemical properties we link to Relativistic quantum chemistry, where for the other (substantially heavier) elements I've reviewed we've linked to Spin–orbit interaction, these seem to be discussing a similar phenomenon. Am I missing a distinction?
    • Nope: the spin-orbit interaction is basically the root cause for relativistic effects in chemistry. It's just that in this article, we don't explain everything from the bottom, because there is still a lot to talk about for Ra's chemistry without going into it. For those substantially heavier elements, we know absolutely nothing about their chemistry, so I went very technical to cover all the predictions that had ever been made about them which I could find. Double sharp (talk) 13:26, 8 October 2014 (UTC)
      • Makes perfect sense. Protonk (talk) 15:21, 8 October 2014 (UTC)
  • "and "radium" came to refer to all isotopes, not just 226Th." Do we mean 226Ra?
  • "They found the radioactive compounds to be very similar to the barium compounds, except that they were more insoluble: this enabled them to separate them out and discover a new element in them, radium." Sort of awkwardly worded. e.g. "them" points to different things as the sentence goes on. We're trying to say a few things: 1. the radioactive compounds were very similar to barium, but 2. they were more insoluble, therefore 3. the compounds could be extracted. 4. That extracted compound was a new element, radium. I'd say split the sentence in two and see if it works better.
    • Changed to "The Curies found the radioactive compounds to be very similar to the barium compounds, except that they were more insoluble. This made it possible for the Curies to separate out the radioactive compounds and discover a new element in them, radium."; better? Double sharp (talk) 13:26, 8 October 2014 (UTC)
  • "Tritium emits beta radiation which cannot penetrate the skin, rather than the penetrating gamma radiation of radium and is regarded as safer. It has a half-life of 12 years." Coming on the heels of "safer radioactive promethium" I'm not sure about this sentence. First, alpha decay can't really penetrate the skin, both alpha and beta decay are problematic mainly due to ingestion, with alpha decay being more dangerous because the particles do more damage than beta decay. Second, radium emits gamma radiation, not promethium, so the comparison to gamma radiation might explain why tritium replaced radium but not why it replaced promethium (also AFAIK promethium also decays via beta decay).
    • This is actually a more interesting story than I expected it to be at first! Firstly, tritium being safer makes some sense, because the energy released by the beta decay of 147Pm is an order of magnitude higher than that released by 3H. However, tritium is a gas, so containment is an issue: so Pm is actually still used today for specialist purposes. Ra is also an alpha emitter, and Pm and H's beta emission won't age the phosphors so much. I still haven't found for sure why tritium has completely eclipsed Pm except when the latter is really necessary, but if I had to guess I would say that it's because tritium is easily made in nuclear reactors and can be collected as a byproduct, whereas promethium can't be made as a byproduct – you've got to actively go out and make it. Double sharp (talk) 06:33, 18 October 2014 (UTC)
      • OK, I've tried to make it read that both Pm and T have replaced Ra. This is true, although T is more common than Pm and Pm only gets brought out when it is absolutely needed. I think it's better now. Double sharp (talk) 06:30, 2 December 2014 (UTC)


  • do we have a better source for the naming of radium than this?
  • Not required for the GA review but JSTOR 986549 is a fun read and has some color on the early popular history of Radium. Interestingly enough, the article notes that an early popularizer of radium, William Hammer, gave an estimate of ~5 thousand tons of uranium ore to 1 kg of radium. For an estimate offered in 1904, that's not too far off the 1 ton -> 1/7 of a gram.
  • The historical applications section runs a while without sources and where it is sourced we reference encyclopedia britannica and I actually like the latter source better than britannica, but I think there's more than enough sourcing available on the historical uses of radium to support or supplant both.
  • JSTOR 41821475 might be useful for the early history of the radium industry
  • There are a large number of sources on the early medical use of radium. Apparently both the british and the US set up "national radium institutes" and I think there were more applications than cancer treatement (at least to start)

Thanks, Protonk (talk) 14:27, 4 October 2014 (UTC)

@Protonk: I'm doing some further referencing – so far I've got rid of the citation needed tags, but there are still some places that need refs. I'll post again when it's done. In the meantime, I'll have a look through this and see what I can use from here. Double sharp (talk) 16:00, 21 November 2014 (UTC)
Ok. Ping me when you want me to take another look. If you want I can gopher around for some more sources. Protonk (talk) 18:37, 21 November 2014 (UTC)
@Protonk: Can you help me gopher around for more sources? Most of the things I usually can find talk more about the chemistry of the element than its history, which is fine in most cases, but for an element like Ra it is really irritating for writing the "history" section. Double sharp (talk) 13:25, 29 November 2014 (UTC)
@Protonk: OK – now it looks like everything might be sourced – but I will try to look for more sources and make it more watertight. In the meantime, if you find any sources, please add them to the article. Double sharp (talk) 14:15, 4 December 2014 (UTC)
@Double sharp: Sorry about not getting back to this. I'll take a look this weekend and add sources and complete the review. Thanks for being patient! Protonk (talk) 15:24, 4 December 2014 (UTC)

followup gophering[edit]

  • As I mentioned above, there's the Maria Rentetzi article here. She also wrote a book on the cultural history of radium, full text is available here. I think the book is a pretty solid reference (it's reviewed here so it's not some wildcat ebook.
    • I dunno about most of this. It's a very solid reference, no doubt, but most of it is about the general story of radioactivity, which of course touches on Ra, but Ra is not the focus. I think this would fit much better in an article like history of radioactivity (?! I expected that to be blue). Double sharp (talk) 14:20, 8 December 2014 (UTC)
      • There very much needs to be something like the history of radioactivity. Protonk (talk) 16:25, 8 December 2014 (UTC)
        • Indeed there does. (Very much hoping that the redlink is not because we really don't have an article, but because nobody thought of this plausible redirect.) Double sharp (talk) 04:40, 9 December 2014 (UTC)
  • there's a fairly recent article on the history of radium quackery here (that's not full text but you can find a pdf easily by googling).
    • This is such a huge topic! Maybe we should just leave a summary here and put the meat at the article on radioactive quackery. Double sharp (talk) 14:28, 8 December 2014 (UTC)
    • Is this the pdf in question? Double sharp (talk) 14:39, 8 December 2014 (UTC)
      • Yeah. Upon re-reading it's mostly about quackery in general. I think I'll look through the sources I've suggested above and make sure that they're focused on radium and try to add some content for those that are. Protonk (talk) 16:25, 8 December 2014 (UTC)
  • ISBN 0549635211 (searchable on google books) has several notes about the early history of radium (including the formation of various radium trusts). I can find specific pages (or screencap them if for whatever reason gbooks changes their mind about viewability)
  • this is an older review article, but it has some information on how health information regarding radium propagated within the medical community.

I'll add a bit more later. I think we could probably (eventually) break out a history of radium article and I don't want to recommend that you overload it, but it's so central I figure the above is a good balance. Protonk (talk) 17:38, 7 December 2014 (UTC)

OK, I'll add these.
P.S. I'm going on an internetless holiday from 13–24 Dec, so if we're (OMG!) still not done by then, I'll try to get everything resolved once I'm back. (And hopefully we will not break the record for the longest GA review.) Double sharp (talk) 14:18, 8 December 2014 (UTC)
I think we're in the running for top 10, at least. :)
@Protonk: You know, while improving and creating all those history-of-radium subarticles is a good idea, maybe we can sabotage our aim at the longest GAN record by leaving that to after the review. :-P Double sharp (talk) 05:58, 10 December 2014 (UTC)

@Protonk: All right, I'm back – gonna do some work tomorrow (and hopefully wrap this up in time for 2015!). :-) Double sharp (talk) 15:52, 26 December 2014 (UTC)

[1] (you might have posted this already?) Double sharp (talk) 14:51, 27 December 2014 (UTC)

Drive-by comment[edit]

@Double sharp and Protonk: I don't intend to be rude, but isn't it time to finish up this review? --AmaryllisGardener talk 23:05, 10 January 2015 (UTC)

I have to agree. This review has been going on for 3 months. If no progress is made within 48 hours I will unfortunately close the review.--Dom497 (talk) 00:51, 12 January 2015 (UTC)
I am now closing the review.--Dom497 (talk) 03:25, 14 January 2015 (UTC)