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Good article Berkelium 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.
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Article changed over to new Wikipedia:WikiProject Elements format by mav 09:46, 3 Apr 2004 (UTC). Elementbox converted 11:42, 17 July 2005 by Femto (previous revision was that of 19:41, 4 July 2005).

Information Sources[edit]

Some of the text in this entry was rewritten from Los Alamos National Laboratory - Berkelium. Additional text was taken directly from the Elements database 20001107 (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.


Was this element named after Berkeley, California, or the University of California, Berkeley?  – Jrdioko (Talk) 23:10, Apr 26, 2004 (UTC)

I've heard its Cal. —Preceding unsigned comment added by (talk) 07:13, 13 September 2008 (UTC)

redirect from bk[edit]

ok, who redirected "bk" to this? i wanted burger king not some wierd nerd thing —The preceding unsigned comment was added by (talkcontribs) .

No, it should redirect here. Bk is the chemical symbol for berkelium, and that is the most important use of Bk. If some other important use came along it should become a disambiguation page but untill that time, Bk should redirect here. Polonium 23:29, 30 June 2006 (UTC)
How dare you call us weird nerds. I consider myself a weird geek, actually. You'll have to search for "Burger King", or the BK (disambiguation) page is the best you can get. The primary use of Bk (uncapitalized k) is berkelium. Though if there's a redirect, there should also be a disambiguation, added one to this article. Femto 11:21, 1 July 2006 (UTC)
How dare you call us weird geeks. I consider myself a perfectly normal geek, actually.Njaohnt (talk) 00:25, 28 August 2012 (UTC)
Three against one dude. Berkelium is an amazing element, more amazing than any other BK. Why did you want to know about Burger King anyway? Njaohnt (talk) 00:25, 28 August 2012 (UTC)


What does it look like? Why is there no picture? --Ferocious Flying Ferrets 03:05, 16 March 2010 (UTC)

There's a picture now.Njaohnt (talk) 23:40, 5 September 2012 (UTC)

GA Review[edit]

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

Reviewer: R8R Gtrs (talk) 17:49, 3 April 2011 (UTC)

I'll review the article--R8R Gtrs (talk) 17:49, 3 April 2011 (UTC)

GA review – see WP:WIAGA for criteria

  1. Is it reasonably well written?
    A. Prose quality:
    B. MoS compliance for lead, layout, words to watch, fiction, and lists:
  2. Is it factually accurate and verifiable?
    A. References to sources:
    B. Citation of reliable sources where necessary:
    C. No original research:
  3. Is it broad in its coverage?
    A. Major aspects:
    B. Focused:
  4. Is it neutral?
    Fair representation without bias:
  5. Is it stable?
    No edit wars, etc:
  6. Does it contain images to illustrate the topic?
    A. Images are copyright tagged, and non-free images have fair use rationales:
    B. Images are provided where possible and appropriate, with suitable captions:
  7. Overall:
    Pass or Fail:

As I go on reviewing, the table will be filled more. Something isn't filled. Be patient :)

  • I've found a capture that seems not so good to me: "Double-hexagonal close packing with the layer sequence ABAC in the crystal structure of α-americium (A: green, B: blue, C: red)." Why americium is here?
    • done
  • "1 M sodium hydroxide solutions" what M is?
    • done
  • it mentions two compound that seem to be Bk(I), (BkNO3)3·4H2O and Bk2O, but this isn't reflected in the infobox. The infobox should be updated, or this clarified.
    • good catches
  • some images lack alt texts and the one with curves lacks author
    • improved all, added authors. Nergaal (talk) 02:14, 6 April 2011 (UTC)
  • "space group P63/mmc, lattice parameters of a = 341.6 pm and c = 1106.9 pm." could this and other space groups be rewritten in some way to make this at least a bit understandable?
    • This is a bit tricky. "(space group C2/c, lattice constants a = 1247 pm, b = 1058 pm, c = 817 pm)" was before " (Pearson symbol mS60, space group C2/c No. 15, lattice constants a = 1247 pm, b = 1058 pm, c = 817 pm)". The space group describes the symmetry of the crystals, while the lattice parameters describe the size of the repeating units. I am not sure how to change the presentation without removing the information (otherwise really important to describe the structure) completely. Nergaal (talk) 02:19, 6 April 2011 (UTC)
      Space group and lattice constants are needed to describe the crystal symmetry for those who want to compare it with other elements, even without knowing what those symbols mean - simplifying it to, e.g., "hexagonal" is same as calling tiger shark as shark. Pearson symbols can be safely removed (an alternative presentation); space group No. can be removed, but is not redundant - a simple example why: many cubic crystals have same symmetry (e.g. Fm3m) but different unit cell size and thus different space group No. Materialscientist (talk) 06:20, 6 April 2011 (UTC)
      R u sure that the number is dependent on the cell size? Nergaal (talk) 14:25, 6 April 2011 (UTC)
      Different number merely tells that the cell is different, within the same symmetry. The difference might be in the cell size or in some other parameter. PS. Sorry "cell size" meant "number of atoms per unit cell, surely not just the a,b,c, values - I better not use this confusing term. Materialscientist (talk) 02:50, 7 April 2011 (UTC)
      Maybe, you should instead briefly describe the symmetry? I'm not sure that most readers require space groups. Also, about lattice constants. Maybe instead of "lattice constants a = 1247 pm, b = 1058 pm, c = 817 pm" this could go as "lattice constants of 1247, 1058 and 817 pm"?
      Symmetry is a good idea (thinking), "lattice constants of" is not - the a,b,c, notation conventionally identified the high-symmetry c axis which can't be worked out from the numbers alone (the largest is usually c but not always). Materialscientist (talk) 00:34, 7 April 2011 (UTC)

<indent>Sorry, I missed the split to Compounds of berkelium. Indeed, all technical details can be kept there and removed from the berkelium article, and I've done (some of) that Materialscientist (talk) 01:08, 7 April 2011 (UTC)

    • That was exactly my plan I just had to leave from de computer for a few hours. Thanks for taking care of it. Nergaal (talk) 03:52, 7 April 2011 (UTC)
  • Link GPa to gigapascal?
    • done
  • "Ag(I)-S2O82–" this is Ag2S2O8, right? Also, it would sweet to expand Bk to berkelium, Ag2S2O8 to silver(I) peroxydisulfate, 251
    to californium-251 and so on, at least where it is easy. I don't think most readers understand what 251
    is for, and that all known the principles of chemical formulae like, say, Cr2O72–, which is easily replaced with "dichromate ion"
    Not to bug you, but I believe this logic is rather questionable: only a a chemist would understand complex terms like "silver(I) peroxydisulfate", but most people have enough education to read Ag2S2O8. A compromise could be to use the formula and wikilink it or give both names. For isotope names, it is acceptable to use californium-251 and 251Cf in the same article (but not Cf-251), but better keep one style within one subsection. Normally the isotope section is written using the 251Cf style. Materialscientist (talk) 06:20, 6 April 2011 (UTC)
    • reduced the short-hand usage significantly Nergaal (talk) 02:01, 6 April 2011 (UTC)
  • "Bk[8] and O[4]" meaning of this can be guessed, but that's not what we like. In fact, the best about the whole coordination numbers stuff could be first appearing "n-coordinated" replaced with "n-coordinated (coordinated with n other atoms)"(or molecules, see context) and then everywhere state only "n-coordinated"
    • fixed

To be continued--R8R Gtrs (talk) 18:58, 5 April 2011 (UTC)

  • Compounds

all compounds have lattice parameters, but it doesn't look like they're really notable. The whole section.

A compound exists, maybe has a color. Lattice parameters. Next compound.
See above. Materialscientist (talk) 01:08, 7 April 2011 (UTC)
  • "berkelium(IV) chloride Cs2BkCl6" I'd like all compounds like that to have full names, caesium berkelium(IV) hexachloride. Also, I'm doubtful of "berkelium(III) chloride, Cs2NaBkCl3"
    Please see above. Consider caesium sodium berkelium(III) trichloride and Cs2NaBkCl3. I argue that the former is quite incomprehensible and the latter is clear. Granted, the former gives oxidation state which needs to be worked out in the formula case, but the composition is primary and is hard to grasp from the former. Materialscientist (talk) 00:34, 7 April 2011 (UTC)
    That's not in the article anymore, but I'll explain. I want to see both name and formula, that'd probably be the best. About Cs2NaBkCl3, the only thing I don't like is the formula. Since it's a Bk(III) compound, I think it should be Cs2NaBkCl6 (the way it's also mentioned in the table) These are now only tips for compounds of berkelium.
  • There are several refs like "Peterson, p. 34", but there's more than one ref from Peterson
    It was Ok (notes are to be looked in the bibliography), but I've set up Harvard linking for clarity. Materialscientist (talk) 00:34, 7 April 2011 (UTC)
    My bad. But thanks for doing this! It wasn't for nothing since it got better--R8R Gtrs (talk) 14:28, 8 April 2011 (UTC)
  • "Bk2O2S, Bk(NO3)3·4H2O, BkCl3·6H2O, Bk2(SO4)3·12H2O and Bk2(C2O4)3·4H2O." again a list of compounds referred only by formula, which I'd like to see the way name (formula)
    Done. Nergaal (talk) 23:34, 8 April 2011 (UTC)

As of now, it's the only thing I don't like. I'll check the article again and then I'll award GA--R8R Gtrs (talk) 14:28, 8 April 2011 (UTC)

OK, nothing keeps me from not listing the article as a GA, so here it goes! Thanks for your work! Please, make sure not to leave the article now. At least americium to einsteinium articles have the potential for future FAC--R8R Gtrs (talk) 12:12, 9 April 2011 (UTC)

More information[edit]

These could possibly be included into the article:

Double sharp (talk) 12:54, 19 January 2012 (UTC)

We tend to avoid anecdotes and similar trivia in elements articles. All elements had some alternative names before the primary one was accepted. Yet only notable ones are included. Etymology of foreign language names should probably be covered in respective wikis. Materialscientist (talk) 13:01, 19 January 2012 (UTC)

R8R Gtrs comments[edit]

I just read (gave it a deep read) a few sections. There are things to be done, and some even may require some, well, work, although it won't be very scary (wouldn't be for me at least). I'll try not to just point the problems I find, but to explain and maybe go off the topic to make it easier, this was building in my head up while reading. I'll start off with writing some of these days.--R8R Gtrs (talk) 19:12, 22 August 2012 (UTC)

In general, don't follow simple comments like "too wordy." I'm referring to the Mav's comment. The other thing is, he explained his point, and it kinda makes sense, below... but don't get yourself immediately scissors and cut everything. If having such comments, always ask for exact advice. Don't be an asshole and reask everything, simply don't follow general comments. Also, don't be afraid to resist, but don't resist everything. Use judgment. Think if the complainer realizes the situation, think if it's a good catch (needs to be fixed/a bad wording, etc.). Many "bad" things are done by intention. Don't hesitate to explain your point. Most commenters will understand. And it'll add you a few points. These are just a few tips. Also, californium is really good... I'll steal a few ideas from there.

But I will also state I see nothing wrong in general in big articles (despite praising californium). Depends on the subject actually. And big treasure is better than small shit, but small treasure is better than big shit. The article with my points implemented may remain big or get as small as californium, I'll find out later what could be useful. But what I'm pointing to is, the number of bytes is not the point.

For you to understand better what this is: this is a reader's (as opposed to editor's) expierience, with some suggestions. I did not get deep into the topic (any deeper than the article)


The History section.... It worries me a little, even though won't have to use much work. It was pointed (reasonably) to be too big and to describe only the discovery. The easiest solution would be retitling the section ("Discovery"). Although I don't like the easiest solutions (not always the bast), this one will probably do. If the article is right that it has no real uses, there have been no controversities, then probably no history either. But I want you to be sure in that.

There is another approach, and it will also work. Adopt a californium-like section structure. It probably isn't very hard to it with info like date of first compound production.(Gazillion of books by Seaborg and similar people are available at Google Books. Consider checking element biographies in the biggest element chem sourcebooks (Wiberg, Greenwood, etc.) Don't forget those PDF lying somewhere in the WP Elements archives... What if?) In fact, I'm beginning to think you could combine the two (History section with Discovery and Post-discovery developments)

Probably you could describe the story of the PT at the point. (something like "All stable elements have been discovered by 1930, and the heaviest then-known element was uranium (element 92). However, as the science developed, the known, and later the unknown elements were artificially synthesized, with the first one being technetium. After chemical studies on neptunium (element 93) and plutonium (94), Seaborg proposed the actinide chemical series, with element 97 being a heavier homolog of terbium." and only then going up to the point "could've been synthesized before, but the discovery date is...." because if you lack a neat history of the thing, tell a history of a larger thing. It is a good presentation rule, use it. Shouldn't be very hard actually. Also, since you tell the story of chemical identification, it may go before naming, which is obviously the last thing tin the discovery. It's a first impression on the section, more may come--R8R Gtrs (talk) 19:01, 24 August 2012 (UTC)--R8R Gtrs (talk) 19:01, 24 August 2012 (UTC)

About discovery details, feel free to cut them. While I understand the stuff, it makes me sick. I'll show an approximate treatment of one para, try to do the rest by yourself:

The most difficult steps in the synthesis of berkelium were its separation from the final products and the production of sufficient quantities of americium for the target material.(You'll point that in the relevant point, after you tell how you got the final products) First, americium (241Am) nitrate solution was coated on a platinum foil, the solution was evaporated and the residue converted by annealing to americium dioxide (AmO2).(What's the point of mentioning the nitrate and platinum (won't use/a detail)?) This target was irradiated with 35 MeV alpha particles for 6 hours in the 60-inch cyclotron at the Lawrence Radiation Laboratory, University of California, Berkeley.(boring!! Without explaining why we even need to know the value, it won't work as too technical. What's the point of 6 hours? How do 60 inches help? If can't reply fast, don't try to. Expect a painter as a reader. And we already mentioned Berkeley!) The (α,2n) reaction induced by the irradiation yielded the 243Bk isotope and two free neutrons:[2](simply say nuclear, will cut no info by that, since you have the equation)

Remember you'll be telling such stuff in the Production section, where it will be more relevant. There are few cases when you really need to explain the MeV particle energy, though. Don't forget about your reader. He don't need centrifugation or chromatography. Try to do it as if you were to explain it your friend. (Always remember: you can't mess in the first sections with scientific stuff. Only after you have the reader. And even then you can't relax. But first section are trice important)--R8R Gtrs (talk) 20:00, 24 August 2012 (UTC)


Before I go, I'd rather suggest to put it as the first section. you may disagree. I'm giving you an idea. Figure out your own pros and cons, and go ahead.

I saw a comment, "Compares with Cm and Cf, why is it relevant?" Admit it's a good catch. Could've missed myself. I'd rather suggest something like, "Berkelium is the element 97, located in the center of the actinide series. The actinides past (what? Plutonium? Check the data) have similar properties, with slight trends shown along the group." i like it slightly better than the current version. and then smoothly penetrating into stuff. You'll need a ref, though. I also see Bk values are closer to Cf than Cm, is there a reason? Also, you'll have to explain bulk moduli (I had no idea of what it is before I checked. Define in the artilcle, using parentheses) Also, the third para is way too nerdy. Define in parentheses each blue linked word, decide what can go bye bye. Specialists don't use Wiki as their primary info source, so it's OK.--R8R Gtrs (talk) 22:01, 25 August 2012 (UTC)

Allotropes stuff is even nerdier. I would suggest cutting most info. But dunno how would one implement. think what is right for you.

(omitting chemical for now)

I would probably write more on Isotopes. I'd maybe do it in a big way (see astatine); californium offers a good way as well.

Good about primordial Bk, but would to have a source (will be an easy find). The rest of the subsection will probably do.


The isotope 248Bk -- cut everything since the point, unused isotopes, forget about them. I'm also feeling there are too many nuclear reaction equations, but dunno what to do about it.

You probably don't need the list of oxidizers. Don't think this section will raise many question otherwise

Chemical and compounds[edit]

Think that for an element like this I'd suggest merging the two (which would include cutting compounds info) I would maybe organize it this way: Para 1 -- reactivity (also close-check Compounds section, for info like elevated-t Bk + N2/P4/As/Sb reactions), para 2 -- ions (think you got enough info), and then some small compounds talk (ionicity degree and such stuff). Or use the structure like indium (that's at least the size I think is bingo). I don't think californium is the best in this respect.--R8R Gtrs (talk) 13:10, 26 August 2012 (UTC)


Is kinda small, seems OK? Weird that a single sciencecraft experiment makes as much in letters as all others together, though.

Nuclear cycle[edit]

The first sentence was good, but the second one... Again these figures people including me don't understand. Give comparisons or cut. Also, you maybe list too long a list of 247Bk critical masses (I would use only the smallest one)


Huh! Seems good.--R8R Gtrs (talk) 22:59, 25 August 2012 (UTC)

overall and advice (if I come up with it, much's been written before)[edit]

In general, over a half of this article is fine (has no big issues). With my recommendations implemented, it's gonna be a great article. It may take a couple of weeks of work, but then it should have no big problems. Don't forget that it's one opinion, though. Also think I was writing too wordy the first sections, tried to do the rest shorter (not to scare you away). Also close-check the ref formatting (sooo gonna be an issue during FAC). After the FAC, I strongly recommend you to write a heavy-impacting article to get a star (sodium, iron, gold, chlorine, etc., although I'd love you not to pick aluminium, I'm thinking about it myself, planning to write it in 2013), it'll be a reader-good thing and will get you much of experience.

If you're having serious problems with it, ask for help. Try personally, it's more useful, as you can see (it's how you got me). If having serious problems with the FAC, also post at the project talkpage. Good luck with the article--R8R Gtrs (talk) 13:40, 26 August 2012 (UTC)

Why is this listed as a WP:University article?[edit]

Doesn't seem to fit the mold other than the name's reference to a school. Buffs (talk) 18:04, 24 August 2012 (UTC)

Probably because the element was discovered at that university. Double sharp (talk) 05:20, 25 August 2012 (UTC)


I heard something about this element being retracted because they made a mistake when they thought they made itSaxophonemn (talk) 20:33, 20 November 2013 (UTC)

I never heard of such a thing for this particular element. Source? Double sharp (talk) 02:07, 21 November 2013 (UTC)

Natural occurrence[edit]

This article cites the only source I've ever seen claim that natural berkelium might exist, and it doesn't cite any outside source nor does it state that any natural berkelium has ever been detected. It's not implausible that it might occur by neutron capture, but has there ever actually been any detection of it in nature, or any other transplutonium element in nature? If not, should Wikipedia be making this claim? - Bootstoots (talk) 18:05, 6 May 2015 (UTC)


Is it "berk'-lee-um" or "ber-kel'-ee-um"? DMacks (talk) 05:53, 8 September 2015 (UTC)