[MSA-talk] R: Birchite

Marco Ciriotti m.ciriotti at tin.it
Thu May 29 05:19:58 EDT 2014

"Bridgmanite" is the name already used for the new mineral with composition
MgSiO3 (orth	Pnma	5.02	6.90	4.81) characterized by Tschauner &
Ma from the Tenham (chondrite) meteorite.
The voting for the approval of this new phase by the members of the IMA
CNMNC is current.
Birchite is an already IMA approved mineral with composition
Cd2Cu2(PO4)2(SO4)·5H2O (orth	Pnma	20.8938	6.1640	10.4768) and
published by Elliott P., Brugger J., Pring A., Cole M., Willis A., and
Kolitsch U. (2008) on American Mineralogist, 93, 910-917. 
Marco E. Ciriotti

-----Messaggio originale-----
Da: msa-talk-bounces at minlists.org [mailto:msa-talk-bounces at minlists.org] Per
conto di Frank Spera
Inviato: giovedì 29 maggio 2014 01:49
A: Anton Chakhmouradian
Cc: msa-talk at minlists.org
Oggetto: Re: [MSA-talk] Birchite

it is interesting and surprising that there is not already a mineral called
bridgmanite, or something along these lines. Considering the enormous
contributions he made to what we call mineral physics, it seems like a
glaring omission. i realize all the rules etc etc but we have jimthompsonite
and ringwoodite and a host of others. Why no bridgmanite?

does anyone know why this is the case?


Quoting Anton Chakhmouradian <Anton.Chakhmouradian at umanitoba.ca>:

> A few clarifications to some of the previous e-mails, if I may:
> -          Something does not have to exist at the Earth?s surface  
> (or be stable under ambient conditions) to qualify as a valid mineral 
> species. Prior to the recent report from Australia published in 
> Geology, tranquilityite, for example, was known only from lunar rocks. 
> Akimotoite and ringwoodite are not stable at the surface, but do 
> represent valid minerals.
> -          The current CNMNC rules are actually quite reasonable ?  
> see, for example, the description of barioperovskite in AmMin (vol.  
> 93, p. 154), where individual grains were < 10 microns in size.  
> Browsing through the approvals of the past few years, the two key 
> requirements seem to be compositional and structural data (or, at 
> least, a convincing enough diffraction pattern demonstrating 
> uniqueness of the material).
> -          Although it is indeed the prerogative of the discoverer  
> to propose a fitting name, the CNMNC members do provide feedback on 
> both the mineral AND THE NAME. And these members are supposed to 
> represent us in that capacity, not strictly speaking just their 
> personal opinion. (That is the reason why their names are accompanied 
> by little state flags on the CNMNC page.) I am not sure how much of 
> that supposed feedback has been sought by each individual member, but 
> that is certainly something we all can influence and, potentially, 
> change. I do agree that choosing the name for two of the most common 
> minerals on this planet (MgSiO3 +
> CaSiO3 ?perovskites?) should be an international endeavour, 
> particularly given the tremendous collective INTERNATIONAL effort that 
> has been invested in their study to date.
> One example where CNMNC exercised their authority on a new mineral 
> name, from the not-so-distant past, is the Ca borate SERBIANITE (or 
> SRBIANITE in the original version), the name that was rejected by IMA 
> (vote 1995-020) on unclear (well, not clear enough to me) grounds and, 
> despite the discoverer?s appeals, has never been approved. The mineral 
> was finally published as JARANDOLITE. I do not mean to politicize this 
> discussion, so anyone interested in this story can find out the 
> details from this Mindat page:
> http://www.mindat.org/mesg-14-24370.html
> Anton Chakhmouradian
> University of Manitoba
> From: msa-talk-bounces at minlists.org
> [mailto:msa-talk-bounces at minlists.org] On Behalf Of David Hirsch
> Sent: Wednesday, May 28, 2014 5:52 PM
> To: Alfredo Petrov; MSA-Talk at lists. minsocam. org
> Subject: Re: [MSA-talk] Birchite
> Alfredo-
> There is the very real possibility that no one will ever find enough 
> material to get the mineral approved by the IMA under the current 
> rules.  Should that be the case, I suggest that the community 
> collectively decide on a name for this material and start using it in 
> lieu of the poor options we have now for speaking and writing about 
> the mantle.  However, based on a private email I received, I would 
> suggest waiting until the next CNMNC Newsletter before setting out to 
> pursue this within the community.
> -Dave
> ============================
> Dave Hirsch
> Associate Professor
> Department of Geology
> Western Washington University
> alternate email: dhirsch at mac.com
> http://www.davehirsch.com
> cell: (360) 389-3583
> work: (360) 650-2166
> fb: http://www.facebook.com/dave.hirsch
> ============================
> From: Alfredo Petrov <alfredo at mindat.org<mailto:alfredo at mindat.org>>
> Date: Wednesday, May 28, 2014 at 3:27 PM
> To: "MSA-Talk at lists. minsocam. org"  
> <msa-talk at minlists.org<mailto:msa-talk at minlists.org>>
> Subject: Re: [MSA-talk] Birchite
> Just a reminder that public advance discussion of whom a mineral 
> species should be named after is not much use, as naming rights belong 
> exclusively to the person who submits the proposal and description to 
> the IMA names commission, and we've no idea who is going to do that, 
> or even whether anyone is going to undertake the procedure at all. 
> [cid:image001.gif at 01CF7A9F.0FB08890]
> On 29 May 2014 06:29, Matthew Kohn
> <mattkohn at boisestate.edu<mailto:mattkohn at boisestate.edu>> wrote:
> Birchite is also a term used for members of the John Birch Society.
> How about...Birchovskite?
> Matt
> On May 28, 2014, at 2:20 PM,
> msa-talk-request at minlists.org<mailto:msa-talk-request at minlists.org>
> wrote:
>> Message: 1
>> Date: Wed, 28 May 2014 20:14:09 +0000
>> From: Anton Chakhmouradian
>> <Anton.Chakhmouradian at umanitoba.ca<mailto:Anton.Chakhmouradian at umanit
>> oba.ca>>
>> To: Frank Spera <spera at geol.ucsb.edu<mailto:spera at geol.ucsb.edu>>,
>> "msa-talk at minlists.org<mailto:msa-talk at minlists.org>"
>>       <msa-talk at minlists.org<mailto:msa-talk at minlists.org>>
>> Subject: Re: [MSA-talk] Mineral name for perovskite-structured (Mg,
>>       Fe) silicate?
>> Message-ID:
>> <5CB931DE61731344B9C43E02E7E530F4B5CC2BFC at UMCE3EXMD02.ad.umanitoba.ca
>> <mailto:5CB931DE61731344B9C43E02E7E530F4B5CC2BFC at UMCE3EXMD02.ad.umani
>> toba.ca>>
>> Content-Type: text/plain; charset="utf-8"
>> It is a bit ?unfortunate? that LINGUNITE is already taken (thank you, 
>> Thomas, for ?chiming in?). So is BIRCHITE, actually (Ca-Cd 
>> phospho-sulfate), but named after William Birch of Victoria Museum.
>> There has been a very good succinct retrospect published on mineral 
>> physics in Sciences of the Earth (ed. by Good, 1998); see under 
>> ?Matter, Properties...?  (pp. 523-535). Plenty of deserving people 
>> have not been ?mineralized? yet!
>> Anton Chakhmouradian
>> University of Manitoba
>> From: Frank Spera 
>> [mailto:spera at geol.ucsb.edu<mailto:spera at geol.ucsb.edu>]
>> Sent: Wednesday, May 28, 2014 10:51 AM
>> To: Thomas Sharp
>> Cc: Anton Chakhmouradian;
>> msa-talk at minlists.org<mailto:msa-talk at minlists.org>
>> Subject: Re: [MSA-talk] Mineral name for perovskite-structured (Mg,
>> Fe) silicate?
>> Call it birchite unless already used to honor the guy who more or 
>> less started mineral physics based on Bridgman foundations Fs
>> Sent from my iPhone
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