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Good articlePromethium has been listed as one of the Natural sciences good articles under the good article criteria. If you can improve it further, please do so. If it no longer meets these criteria, you can reassess it.
Article milestones
February 27, 2012Good article nomineeListed


Article changed over to new Wikipedia:WikiProject Elements format by schnee. Elementbox converted 11:09, 10 July 2005 by Femto (previous revision was that of 13:31, 9 July 2005). 9 July 2005

semi-stable isotope[edit]

OK, what is a semi-stable isotope? —The preceding unsigned comment was added by (talk) 22:32, 5 December 2006 (UTC).[reply]

I would think it's an isotope of a particular element that is still radioactive, but is relatively stable (has a long half-life) compared to other radioactive isotopes. You might find more answers on other pages. AstroHurricane001 22:53, 5 December 2006 (UTC)[reply]
A semistable isotope is one like bismuth-209, element-83, which has

a half-life estimated at about 10^23 years. A tiny bit of alpha decay has been observed in "miraculous" experiments done in exotic semiconductors at temperatures close to absolute zero. 10^23 years is far longer than the life of the known universe, and it used to be thought that bismuth-209 was stable. (talk) 08:38, 8 February 2017 (UTC)[reply]


This article states the appearance but does not have a picture of the element. This is peculiar. — Preceding unsigned comment added by (talk) 05:15, 24 April 2014 (UTC)[reply]

Yes, we're aware of this problem, and we've been looking for a reliable one for years. (Hence the banner at the top of this talk page with the camera in it, requesting a photograph.) Unfortunately, nobody seems to have actually photographed something that is incontrovertibly a pure promethium sample, and therefore there is no image of pure Pm metal on this article. (We do have one for promethium(III) oxide, though.) Double sharp (talk) 12:44, 24 April 2014 (UTC)[reply]

I found a few pictures (they may be fake) of promethium. They all occur on more than one webpage, all stating that they are promethium. Do you think they are reliable: http://www.twnree.com/wp-content/uploads/2012/02/61-Promethium.jpg http://businesslife.ba.com/Media/images/rareh-Business-Life-Promethium-credit-periodictable.com-043410ea-8348-4a28-b7cd-aa244d51c5ee-0-450x521.jpg -- (talk) 23:19, 22 January 2015 (UTC)[reply]

No. [1] is Nd by T.W. Gray [2], and [3] is a colored/decolorized illustration from [4]. Materialscientist (talk) 23:24, 22 January 2015 (UTC)[reply]

I found these images from Chinese websites. I don't know how reliable they is: http://mmbiz.qpic.cn/mmbiz/07vbMHVhyHe9Xa8NzB5iaibFeicn3IPxOmdLljo4hezeQcViaJfa1o8RM9MO2LgwnWnTRYlAs93Ccmk3o0FFOicmXGQ/0 http://a2.att.hudong.com/44/03/01300001385827133437036291016_s.jpg (talk) 08:43, 12 June 2015 (UTC)[reply]

The first one is a Nd-Fe-B magnet according to the caption. The second is the picture of Nd used in Ralph Lapp's book Matter with a recoloured background. Double sharp (talk) 19:33, 12 June 2015 (UTC)[reply]

I found the first image from this website, where all images have the same watermark: http://mp.weixin.qq.com/mp/appmsg/show?__biz=MzA5MTMyODAzOA==&appmsgid=200025081&itemidx=1&sign=18d5b6ffdee5643be61983d6d9170022&3rd=MzA3MDU4NTYzMw==&scene=6#wechat_redirect —  LL221W (talk) 11:15, 13 June 2015 (UTC)[reply]

Yes, but for such a rare element, I'd expect a long explanation of how the sample was made, which I don't see there. (And I'd expect larger safety precautions, as Pm stored out in the open in such large quantities is going to cause heavy radioactive contamination.) And given that most pictures of Pm online happen to be actually Nd, I'm really not convinced by this picture, and probably won't be until it can be proven to be unquestionably Pm. Double sharp (talk) 10:40, 15 June 2015 (UTC)[reply]
Hello, Promethium. You have new messages at Double sharp's talk page.
You can remove this notice at any time by removing the {{Talkback}} or {{Tb}} template.

I found a image is about promethium sample, but I'm not sure that it's real. The image was made by T. W. Gray, too. But when I uploaded this image to Chinese Wikipedia...yes it will be deleted. It's on the Files for discussion now, see zh:Wikipedia:檔案存廢討論/記錄/2022/02/10#File:Promethium_sample.jpg for more information. Oh guys, I've forgotten to tell you the source of this image is https://periodictable.com/Items/061.2/index.html . --ERS ROHU (talk) 12:00, 10 February 2022 (UTC)[reply]

Name change - when and why?[edit]

When did its name change from prometheum to promethium, and why? I'm sure I remember as a kid (late 1970s) the -eum spelling ... - David Gerard (talk) 20:24, 3 January 2016 (UTC)[reply]

My question is was it ever publicly referred to as "prometheum"? My reading of this article is that the name was derived from Prometheus but that the second "e" was changed to "i" when the element name was proposed and that this "-ium" spelling is all that was ever published. However, without reading the actual source I can't be sure. If my reading is correct, there is no need for the "formerly prometheum" note as that spelling would never have really existed.--Khajidha (talk) 12:44, 15 September 2017 (UTC)[reply]

article contradicts itself re: Pm147 emitting gamma radiation[edit]

the first paragraph of Applications says that Pm147 can not emit gamma radiation, and the first paragraph of Precautions says that it can. i'm not sure which is correct, hopefully someone else can revise. WordsAndNumbers (talk) 05:30, 15 October 2021 (UTC)[reply]