Talk:Rare-earth element

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Uses and applications[edit]

It would be interesting to have a paragraph on where rare earths are used to give a bit more context. As it is the article is quite technical, but does not give a good idea of why they are important. — Preceding unsigned comment added by Christian.benesch (talkcontribs) 15:03, 30 January 2012 (UTC)

Neutrality disputed[edit]

Why is there a dispute over the the neutrality of academic conference proceedings? Whitetail 31 (talk) 17:17, 19 April 2008 (UTC)

There is no dispute over the ceredibility of the USGS Fact Sheet citations, there is however a clear bias towards a United States view. There is nothing wrong with this view except that all views should be expressed in equal weighting in order to maintain a neutral point of view, see Wikipedia:Neutral_point_of_view. Specifically: "NPOV requires views to be represented without bias. All editors and all sources have biases — what matters is how we combine them to create a neutral article". Also, the transcripts of an interview by a represenative of the Industrial Minerals Company of Australia (IMCOA) do not make for a credible source of information and clearly indicate the views of the individual / company. The neutrality tag should remain in place until this issue is resolved. Polyamorph (talk) 19:13, 19 April 2008 (UTC)

Added some research. 68.147.5.5 (talk) 22:29, 20 April 2008 (UTC)

Ok, it reads with less bias now, it still needs work though. Thanks Polyamorph (talk) 10:27, 21 April 2008 (UTC)

What to work on? 68.147.5.5 (talk) 15:01, 21 April 2008 (UTC)

Well for starters, only Dysprosium is really discussed. What about the seventeen other elements? There are still citations from an interview which as stated before lacks credibility. The tone of some parts of the section aren't entirely appropriate, e.g. "High Rare Earth prices have wreaked havoc on many rural Chinese villages". There is no discussion of the mining / extraction process itself. The whole section just generally requires more research. Polyamorph (talk) 15:34, 21 April 2008 (UTC)

Cool, I can do that. One question however: how many people actually read this page? —Preceding unsigned comment added by 68.147.5.5 (talk) 18:52, 22 April 2008 (UTC)

So far, in April this year, the article Rare earth element was viewed 5420 times. You can view the statistics here: http://stats.grok.se/ Polyamorph (talk) 20:06, 22 April 2008 (UTC)

Rare Earths In Radiogenic Petrogenesis[edit]

This section could be explained a lot better - "The 147Sm - 143Nd system is joined by the alpha decay of 147 Sm" does not make any sense.Polyamorph (talk) 15:35, 21 April 2008 (UTC)

I removed this since it was incoherently written, seemed to lack an understanding of the scientific principle it was describing and lacked citations. I'm sure there is an of isotopic composition analysis technique that can be applied to rare earths in order to distiguish between the sources of different minerals etc but to be included in the article any description of such techniques must make sense. Polyamorph (talk) 17:18, 22 April 2008 (UTC)

no that kinda makes sense as 147 - 4 = 143. But you are right, there could be a lot of work done. 68.147.5.5 (talk) 18:50, 22 April 2008 (UTC)

nah, you're having a laugh, it doesn't make sense to me and it certainly wouldn't make sense to a layman! Polyamorph (talk) 20:01, 22 April 2008 (UTC)

The Sm/Nd geochronology page is here: http://en.wikipedia.org/wiki/Samarium-neodymium_dating Why not link it? Cwmagee (talk) 11:25, 23 April 2010 (UTC)

Needs better intro[edit]

Too many science articles on WP these days require reading well past the first paragraph to gain a basic understanding of the term being discussed. An encyclopaedic article should always start with a précis of the topic in the first sentence, so that a layperson or casual researcher who is simply following explanatory links need not endure swathes of text (often in hideous techno-jargon, though thankfully not in this case) in order to know roughly what a given term means.

In this particular case, we need to explain the term 'rare earth' in the first sentence, as that's why most people will come here (to see why they are considered 'rare'). As an example, here's a simple re-arrangement of the existing text in a manner that offers an immediate explanation:

Rare earth elements or rare earth metals are a collection of seventeen chemical elements that were first isolated from uncommon oxide-type minerals (earths) found in Gadolinite extracted from one mine in the village of Ytterby, Sweden.

I stress that this is simply an example of how it could be done in this particular instance. But please note that I dropped the tautological '...in the periodic table...' and feel it should stay dropped. Blitterbug (talk) 20:08, 18 April 2009 (UTC)

I think the current intro and first table are very good.

Cwmagee (talk) 11:29, 23 April 2010 (UTC)

Discovery and early history[edit]

The section describes how several of the elements were isolated, but not all. Absent are dysprosium, europium, holmium, lutetium, promethium, thulium, ytterbium, and in the case of two the text stops short with didymium, and gives no explanation of how that was eventually found to be a mixture of two elements: praseodymium and neodymium. --Redrose64 (talk) 08:34, 27 August 2009 (UTC)

hyphens[edit]

Is "rare-earth" being hyphenated or not. Also with the rare-earth magnet article? —Preceding unsigned comment added by 128.111.119.6 (talk) 21:18, 3 September 2009 (UTC)

My father's university textbook favours the non-hyphen form; it is "rare earth" nearly throughout. There are at least 31 occurrences of "rare earth", and just 4 of "rare-earth", all of the latter being on pages vi & 370.
  • Partington, J.R. (1950) [1921]. A Text-book of Inorganic Chemistry (6th ed.). London: Macmillan. pp. vi,370,803–805,819–823,989. 
Maybe there is no clear ruling. --Redrose64 (talk) 21:43, 3 September 2009 (UTC)
I'd sayt that when it is used as a "compound adjective", it should be hyphenated: "cerium is a rare-earth metal". In other cases it's not: "cerium is a rare earth". See WP:HYPHEN. --Itub (talk) 22:11, 3 September 2009 (UTC)
Yes. Reading again, we have three styles:
  1. "rare earth" - adjective and noun (21 cases);
  2. "rare earth element", "rare earth metal", etc. - two adjectives and a noun (17 cases);
  3. "rare-earth element" - compound adjective and noun (4 cases).
Perhaps style (2) is grammatically incorrect, and these should be style (3). --Redrose64 (talk) 22:33, 3 September 2009 (UTC)

What about the section currently titled "Rare-earth free permanent magnets"? I originally felt the hyphen needed to be moved to between earth and free, but now I think this is an example of a word that needs two hyphens: "Rare-earth-free permanent magnets". Thoughts? AlikaAlex 01:54, 8 April 2015 (UTC)

Why 17[edit]

Just out of curiosity, I would like to learn the naming policy of IUPAC. Out of 17 rare earths three of them are actually group 3 transition metals with an outermost d electron. (scandium, yttrium and lanthanum.) The rest are elements with an outermost f electron. Then, why does IUPAC group all 17 together ? To be sure sure, they are found in the same ore deposits. But is that more important than their electronic configuration ? Nedim Ardoğa (talk) 05:43, 5 October 2009 (UTC)

I think that IUPAC didn't coin this trivial term out of nowhere, but simply described the existing usage. Anyway, electron configurations are sometimes overrated. For example, the early actinoids are chemically more similar to the transition metals than to the lanthanoids (look at an old periodic table and you'll find uranium under tungsten). --Itub (talk) 18:09, 12 October 2009 (UTC)
REE is a historical term to describe a group of elements with common geologic occurrence. Use "Lanthanide" if you are discussing electron shells. For example: Lanthanides are extracted from rare earth minerals.

203.129.57.68 (talk) 11:16, 23 April 2010 (UTC)

Ce, Gd, and Lu also have d electrons. Double sharp (talk) 11:08, 10 July 2014 (UTC)

Geologic distribution[edit]

The preferred geologic terms are light and heavy rare earth elements, abbreviated LREE and HREE. A quick google scholar (or subscription scholarly index) search will show that LREE is more than 100 times more abundant than "cerium earth", a term which is mostly found in historic literature. Cwmagee (talk) 11:35, 23 April 2010 (UTC)

Minor layout quibble[edit]

In the table listing the rare earth metals, why is so much column-width given to the Etymology and so little to common uses? —Preceding unsigned comment added by 158.143.65.19 (talk) 09:33, 1 November 2010 (UTC)

The width's were set values, probably because when the list was created there was not much in the uses common. I have removed the width settings so the column widths should be automatic now. Polyamorph (talk) 12:28, 1 November 2010 (UTC)

Possible Topic Duplication[edit]

I wanted to bring to your attention the existence of

http://en.wikipedia.org/wiki/Rare_earth_mineral

which perhaps could be merged to

http://en.wikipedia.org/wiki/Rare_earth_element

--Johnev (talk) 09:45, 9 November 2010 (UTC)

WP:MERGE proposed. --S. Rich (talk) 14:27, 19 November 2010 (UTC)
I'm removing the merge templates, an element and a mineral are two distinct forms. The two articles should not be merged. Polyamorph (talk) 20:12, 19 November 2010 (UTC)
The topics (REM & REE) have large overlap. (Indeed, "mineral" is used as a synonym in REE.) So a discussion of merger is appropriate.--S. Rich (talk) 21:54, 19 November 2010 (UTC)
You want to waste everyone's time by discussing this? The articles are clearly seperate subjects, this one discussing the element and the other discussing compounds of the element. A no brainer. Polyamorph (talk) 08:24, 20 November 2010 (UTC)
The term mineral that you refer to in this article is referring to the mineral deposits containing rare earth elements. Rare earth elements are not found in any quantity in isolation, always within other minerals. Hence the importance of a seperate mineral page. Polyamorph (talk) 08:39, 20 November 2010 (UTC)
You have much more knowledge about the topic than others, I'm sure. How about clarifying the intro sentences? WRT proposed merger, you could address the question of overlap. (And let others decide for themselves if they want to waste their own time in a discussion -- if a consensus is not reached, then the articles don't get merged. But let the discussion take place.)--S. Rich (talk) 17:21, 20 November 2010 (UTC)
From what I can tell you placed the merger tags on the article without any discussion apart from the original users comment that the two articles existed. It was only after I removed the tags that you decided to comment. I made the decision to remove the merge tags because I do not believe the merge is necessary and discussion on the matter is unwarranted. Per WP:SNOW I do not see the point of flogging such discussions just for the sake of it when the result is obvious from the onset. It is, as I said, a waste of time and effort to do so. As for the question of overlap, the minerals page lists the various different minerals contining rare earths whereas the elements page describes the individual elements. They are seperate articles. Polyamorph (talk) 17:47, 20 November 2010 (UTC)
Per your request I have edited the lead, hopefully the distinction is clearer now. Polyamorph (talk) 18:19, 20 November 2010 (UTC)

raremetalmining.com as EL[edit]

I submit that http://www.raremetalmining.com is a proper EL (not reference). It contains "neutral and accurate material that is relevant to an encyclopedic understanding of the subject and cannot be integrated into the Wikipedia article due to copyright issues, amount of detail (such as professional athlete statistics, movie or television credits, interview transcripts, or online textbooks), or other reasons." WP:ELYES [emphasis added] and does not fit into any WP:ELNO criteria.--S. Rich (talk) 14:25, 19 November 2010 (UTC)

It seems to be an automated spam page. All posts on it are drawn from newswires and other blogs (some may be copyvio, but I do not know). There are google ads and an obtrusive popup on the site. The first user to add the link had a name to suggest a COI & his userpage seems to be spam for some completely unrelated venture. This clearly fails WP:ELNO for 4, 11, and WP:EL#ADV. --Karnesky (talk) 16:07, 19 November 2010 (UTC)
Agreed with Karnesky, it's an excellent example of what we should NOT be linking to. Polyamorph (talk) 20:08, 19 November 2010 (UTC)

I submit that http://www.raremetalmining.com gives examples of uses and applications for the rare metal industry. It containes material, videos, and other information that is necessary for any reader to learn that is researching rare metals, or rare earth elements. R.Mowat (talk) 4:47pm, 19 November 2010 (PST)

It is clearly a spam link and your username suggests you have a conflict of interest. Wikipedia has a strict policy on spam, advertising and what does and does not constitute a reliable source. I suggest you read those policy pages before submitting any more external links. Also, do not remove comments by other users on wikipedia talk pages. Polyamorph (talk) 08:31, 20 November 2010 (UTC)

Topic duplication II[edit]

I have expressed my reasons above as to why Rare earth element and Rare earth mineral are valid seperate articles. However, the two articles Rare earth element and Lanthanide are actually more or less the same subject. At this stage I don't think we should propose a merge but I do think it would be sensible to discuss why these articles need to be seperated. I can see a case in which Rare earth element concentrates on describing the geophysical considerations whereas lanthanides concentrates on the chemistry of the elements. Polyamorph (talk) 08:34, 21 November 2010 (UTC)

We could keep the geochemistry and the difficulties in chemically separating the elements here, and move the lanthanide contraction and the technological applications relying on the accessibility of the f-band there. I think that they are different enough topics that two articles are warranted, but I would support stripping this article of all the lanthanides-only material with {{main}} links. - 2/0 (cont.) 18:08, 22 November 2010 (UTC)
The only difference between the lanthanide and rare earth series is that the latter tends to include Sc an Y. I agree, the only things that really need changing at present is to merging the section Lanthanide #Geochemistry to here and the Rare_earth_element#Technological_applications to the lanthanide article. We already have a table which lists the applications of the elements, which can be expanded, so I don't think we need that section here at all. Then I think we should consider including a hatnote on both articles that makes the distinction clear. Polyamorph (talk) 10:05, 25 November 2010 (UTC)
I have made a start on this. Polyamorph (talk) 11:53, 25 November 2010 (UTC)

Top paragraph[edit]

Currently "The first such mineral discovered was gadolinite, a mixture of cerium, ytterbium, iron, silica, and other elements.". Gadolinite is a compound, not a mixture. Silica is not an element. 82.163.24.100 (talk) 14:01, 16 December 2010 (UTC)

Fixed poor wording, thanks. Vsmith (talk) 15:04, 16 December 2010 (UTC)
Point definitely taken on the imprecise/incorrect wording. However, I don't think it's quite appropriate to have the formula for gadolinite in the introduction; if people are interested in this technical information, they can go to the article on gadolinite. I've reinserted the listing of elements, but with more precision this time.Erudy (talk) 14:53, 17 December 2010 (UTC)

The line "The few economically exploitable deposits are known as rare earth minerals." is not really correct. Such deposits (as with all mineral deposits) are those that contain a sufficient tonnage and mineral grade of, in this case rare earth minerals, to make them economically exploitable. Myall blues (talk) 04:40, 19 October 2012 (UTC)

Similarly the language used in the caption of the photo of rare earth oxides is incorrect. "These rare-earth oxides are used as tracers to determine which parts of a drainage basin are eroding. Clockwise from top center: praseodymium, cerium, lanthanum, neodymium, samarium, and gadolinium." The rare earth oxides shown in the picture contain, respectively, the elements praseodymium, cerium etc. suggest changing the second sentence of the caption to "Clockwise from top centre, they contain the elements: praseodymium, ..." Myall blues (talk) 04:49, 19 October 2012 (UTC)

EU stockpiling[edit]

These two new news might be worth including.

--Stone (talk) 19:39, 6 September 2011 (UTC)

Thanks, I updated the relevant sections to include those references [1]. Polyamorph (talk) 13:01, 7 September 2011 (UTC)

Map request[edit]

Perhaps that a map can be made with the most valuable rare earths for creating devices for making renewable energy. See http://www.treehugger.com/clean-technology/goodbye-fossil-fuel-dependence-hello-rare-earth-dependence.html Can someone post good reference map links, that way we can make a request at Wikipedia's Graphics Lab KVDP (talk) 10:08, 2 March 2012 (UTC)

References[edit]

size comparison[edit]

The photo of the penny on top of a rare-earth ore is ridiculous. A rare-earth ore could be smaller than a penny or as big as an elephant. it depends on houw you cut it. 206.192.35.125 (talk) 15:58, 5 July 2012 (UTC)

It is because a piece of rare earth ore could be more than a meter or less than a centimeter across that the addition of a U.S. penny is helpful. It allows better evaluation of elements of the texture. This picture should be restored to the article. - Fartherred (talk) 01:28, 26 July 2012 (UTC)
There has been no objection so far, so I will restore the previous image of rare earth ore. Discussion is still permitted after the restoration. - Fartherred (talk) 17:23, 30 July 2012 (UTC)
It is because a penny is pictured along with the piece of ore that we can know the piece is 5 inches (12.7 cm) across while we remain ignorant of the fineness of the powder in the picture of powdered oxides. - Fartherred (talk) 17:47, 30 July 2012 (UTC)
Yes it's useful, it demonstrates the size of this particular ore - it's not trying to claim all ore's are that size! Polyamorph (talk) 08:35, 31 July 2012 (UTC)

Asteroids[edit]

http://www.dodlive.mil/index.php/2013/02/armed-with-science-saturday-science-fiction-the-aperture-for-science-future/ “A fact that most people don’t appreciate is that all of our rare Earth metals come from asteroid strikes.”

Huh? First I heard of it. I'd add it, but it's USAF and so a really dubious source. Hcobb (talk) 02:56, 4 February 2013 (UTC)

Appropriateness of mnemonic?[edit]

I find the mnemonic troubling, especially given current affairs coverage in the US relating to campus rape and #DistractinglySexy. However this seems to be attributed to Andrea Sella at UCL. What value does this mnemonic have for the subject, and if it does have value there are at least a dozen variants I can think of that don't suggest all chemists are males who routinely trawling parties looking for drunk European girls to rape. Sounds like something made up to sound witty on a TV show. I like smoothies (talk) 18:41, 30 June 2015 (UTC)

Approaching the issue strictly from a policy-based approach, my question is whether a single mention in an interview is sufficient to show that the mnemonic is in widespread use. Unless there are multiple references, we can't verify that it's a common mnemonic. —C.Fred (talk) 18:45, 30 June 2015 (UTC)

who coined "seltene Erden" or "Rare Earths"[edit]

I could find a Google book from 1853 by Plattner already mentioning "Seltene Erden" [2] but not in the sense it is ment today. The first right looking reference is from Welsbach and is named seletene Erden [3]. The artikle from Brauner [4] from 1882 mentiones raer earths in the titel.

--Stone (talk) 23:29, 22 February 2016 (UTC)

are the actinide series rare earths or not?[edit]

This article excludes them them the list (While a number of other references include them, eg http://www.chemicalelements.com/groups/rareearth.html). Then in the text there is a reference to "actinide rare earths". This should be clarified, probably a note saying some sources count them and some don't. Gjxj (talk) 14:01, 12 July 2016 (UTC)

In the Red Book (2005), p 63-pdf: "collective names ... IUPAC-approved: ... rare earth metals (Sc, Y and the lanthanoids)". That settles it.
However, other relevant sources may use other definitions (possibly historic). Such information can be added to the article indeed (not necessarily to the lede). -DePiep (talk) 10:28, 14 July 2016 (UTC)
The actinides were never considered rare earths, to my knowledge, and the classification would only make sense for Ac. Double sharp (talk) 07:48, 18 July 2016 (UTC)