Talk:Cobalt

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Good articleCobalt 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.
May 24, 2011Good article nomineeListed

The Leader[edit]

says "Cobalt-60 is a commercially important radioisotope, used as a radioactive tracer and for the production of high energy gamma rays."

My experience of the use of cobalt isotopes is that it is cobalt-57 which is used as a tracer in medical applications, not cobalt-60. In the 1970s and 1980s I designed instruments such as the 'Hydragamma-16' to measure traces of the Cobalt-57 used in radioimmunoassay for B12 measurements for example. Because of its shorter half-life, the specific activity of co57 is much higher than that of co60, and the relatively lower energies of the co57 spectrum also make it easier to measure the activity in vitro using small and thus relatively cheap and efficient well-type scintillation counters. See for example

http://www.med.harvard.edu/JPNM/physics/isotopes/Co/Co57/hist.html

http://www.amptek.com/wp-content/uploads/2013/12/cdte_5.png

https://www.aacc.org/community/divisions/history-of-clinical-chemistry/analyzer-listing/1984/hydragamma-16

Untitled[edit]

Article changed over to new Wikipedia:WikiProject Elements format by Dwmyers 16:31 Feb 20, 2003 (UTC). Elementbox converted 14:57, 2 July 2005 by Femto (previous revision was that of 00:39, 15 May 2005). 15 May 2005

Information Sources[edit]

Some of the text in this entry was rewritten from Los Alamos National Laboratory - Cobalt. Additional text was taken directly from USGS Cobalt Statistics and Information, from the Elements database 20001107 (via dict.org), Webster's Revised Unabridged Dictionary (1913) (via dict.org) and WordNet (r) 1.7 (via dict.org). Data for the table was obtained from the sources listed on the subject page and Wikipedia:WikiProject Elements but was reformatted and converted into SI units. —The preceding unsigned comment was added by Dwmyers (talk • contribs) 16:31, 20 February 2003 (UTC)

K.H.J. BUSCHOW (ed.), Handbook of magnetic materials, volume 12, 1999 Elsevier page 126 for the hcp->fcc transition. —The preceding unsigned comment was added by Marc Tobias Wenzel (talk • contribs) 17:01, 20 May 2003 (UTC)

Image of cobalt metal[edit]

Is the image of cobalt metal included in this article really cobalt? I looked online for more images of Cobalt metal and all the other pictures I have seen look much more silvery and much less golden.


Hey Guys

In medical uses of cobalt you should mention its use as an Implant material. Its used as for dental implants when alloyed with chromium and molybdenum, refered to as "CoCrMo" in scientific journals or "Vitalium" as a tradename

cheers

Chris


to-do (if you ask me)[edit]

(partial) I gotta go but there are some things I would have liked to do. In case anyone wants to pick up this torch, or perhaps just to remind myself when I come back:

  • I didn't add a see also section and I personally find them helpful.
  • There were some very bad transitions fairly far up. I made a chemistry section and a mining section so I think it's a bit better, but it probably still needs work. And I noticed that now the *sections* go chemistry then mining then chemistry but I can't deal with that now and at least it's semi-readable.
  • Meant to add in some stuff about the President using the coltan reserves as a piggy bank (more polite than that of course). Here is some of the icij coverage:http://www.dw.com/en/drc-president-joseph-kabila-reformer-or-corrupt-authoritarian/a-36935441
  • I found the chemistry very hard going and did an edit for readability but I am anything but a chemistry expert, so if I introduced an error please feel free to fix.
  • some other interesting and possibly accuate things
    • don't think I conveyed the level of kleptocracy. And those who are too young to have seen it happen probably should be told that all that fghting came down to a fight over the mining resources. In other words the coltan and the cobalt.
  • ACLU's This is What We Die For really should get at least a see also
  • Not sure if the hysteria about the security of the global coltan reserve got adequately conveyed.
  • Might want to look at/link to the wiki page on coltan -- it's another conflict mineral
really gotta go now, later.
Oh hey, I was looking for this earlier: https://qz.com/1100874/panama-papers-how-african-oligarchs-use-colonial-methods-to-plunder-the-continents-wealth/ Elinruby (talk) 07:05, 2 March 2018 (UTC)

Cobalt ore[edit]

This should cover the appearance of cobalt ore, in which cobalt veins are associated with silver deposits, and look pink as high quality ore in rock. -- 70.51.45.46 (talk) 07:44, 16 November 2018 (UTC)

Bone Char as a precaution?[edit]

The last sentence of the article, "Cobalt can be effectively absorbed by charred pigs' bones; however, this process is inhibited by copper and zinc, which have greater affinities to bone char.[120]" - is this really important information? It seems like either it needs more context for how that is a useful property, or it is not useful enough to merit inclusion on the page and should be deleted. 128.138.143.213 (talk) 17:46, 7 December 2018 (UTC)


The Cupels uses in fire assay for precious metals are made of calcined bone, ie bone char. I don't think pork bones have any special properties. It's the tri-calcium phosphate that absorbs the metal, but leftover carbon in the incompletely calcined bone char can act like charcoal. TriCalciumPhoshphate acts like triSodiumPhosphate, that's why TSP was used to clean up leaded paint dust, but TCP is nearly insoluble in water and TSP is easily dissolved, 0.002g/ml vs 12g/ml.

What's "coval"?[edit]

In the section "Democratic Republic of the Congo", I noticed this sentence:

It produced an estimated one third of the total global coval production in 2008.[66]

The source for this is a dead link. The word "coval" is very dubious. Maybe the whole sentence needs to be deleted or replaced. Oaklandguy (talk) 07:16, 8 March 2019 (UTC)

coval - must be meant cobalt[edit]

is the article edit protected, or something? i see no mention of this yet the edit button doesnt show up. pls. clarify/correct "coval". 94.21.63.118 (talk) 14:30, 23 May 2019 (UTC). OK, now i see the semi protected till OCT 2019 mark. so pls, an editor with access, take action. 94.21.63.118 (talk) 14:33, 23 May 2019 (UTC).

 Done Thank you for pointing this out! You can use the {{editsemiprotected}} template to draw other editors' attention on the talk page if something needs correcting on a semi-protected page. Double sharp (talk) 04:25, 24 May 2019 (UTC)

Vitamin B12[edit]

The article states that B12 is only made by bacteria or similar organisms. However, it is also present in seaweed and other algae, and also the comfrey plant. — Preceding unsigned comment added by 78.145.46.216 (talk) 22:44, 17 August 2019 (UTC)

No mention of Cobalt carbide[edit]

cobalt carbide has been studied (eg [1]), and can be purchased [2] - Is it CoC-Co2C-Co3C... or a mix or a 1:1:1 lattice ? - Rod57 (talk) 10:26, 7 November 2019 (UTC)

Copper Sulphate or Cobalt Sulphate?[edit]

The 'extraction' section currently contains the sentence 'The residues are further leached with sulfuric acid, yielding a solution of copper sulfate.' Since the copper should have largely been removed by this stage in the purification, I'm gussing this is a typo for 'cobalt sulfate' but don't know enough to be certain. Urilarim (talk) 23:38, 5 July 2020 (UTC)

 Not done: According to the page's protection level you should be able to edit the page yourself. If you seem to be unable to, please reopen the request with further details. In any case, please only use edit requests for requesting specific changes, not to discuss a possible error. Rummskartoffel (talk) 23:57, 5 July 2020 (UTC)
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