[meteorite-list] Water in space

[Gerald Flaherty]

Holy Cow! Even I am getting a glimmer[i repeat, glimmer] of "understanding". 
I thank you Doug! AND I thank YOU TOM for asking a question that I always 
wanted to ask but was afraid to!! Jerry
----- Original Message ----- 
From: <MexicoDoug at aol.com>
To: <daistiho at hotmail.com>; <Meteorite-list at meteoritecentral.com>
Sent: Wednesday, June 01, 2005 6:30 AM
Subject: Re: [meteorite-list] Water in space


> Tracy L. wrote:
>>Exactly!  Consider the case of copper  carbonate.  In its hydrated form,
>>it is a pretty blue crystal; we  used to use it in our swimming hole in
>>low amounts to kill off algae and  weeds.  In its anhydrous form, it's
>>a greenish powder.  Don't  eat either one; bad.   I'm not akamai enough
>>to guess what  hydrates might be present in meteorites, but I'm pretty
>>sure this is  what is meant by water being present in meteorites,
>>chemically bound  into various minerals, which may be released by
>>heating or chemical  reaction.
>
> A-Hola Tracy, Hmmmm.  The idea that a hydrate is a great  way to stabilize
> water I totally agree with you and the physics of it, so I  follow there. 
> But:
>
> I think you are confusing copper sulfate (pretty hue, light royal blue
> crystals) with copper carbonate and/or copper carbonate hydroxide 
> minerals.
> Copper carbonate does not form a hydrated complex in a chemical  sense, 
> though
> copper carbonate hydroxide might be loosely called "hydrated"  instead of 
> a
> hydroxide, by some fast talking pool chemical salesman (or mystic  jewelry 
> peddler?)
> at local pool store if it is really sold there (?).   Anyway, a hydroxide 
> is
> a different chemical animal than a hydrated complex  containing water 
> which is
> bound by weaker structural or van der waals types of  attraction: that to
> which I think Chris eluded and of main interest here for  water are
> chemical/structural "hydrates".
>
> That chemical hydrated  compound on your mind would likely be Copper 
> Sulfate,
> wouldn't it?  It  forms a pentahydrate = complex with 5 water molecules 
> per
> Copper/Sulfur.   The Copper carbonate might be an undesirable precipitate 
> in
> the swimming hole  produced from interaction of copper sulfate with lime 
> or
> disolved carbon dioxide  I bet, and it might be a yucky green?
>
> Copper Sulfate (a.k.a., synthetic  chalcanthite) is a beautiful lab 
> example
> of a stable hydrated complex to at  least +150 C.  It is quite possible it
> could appear in trace quantities in  meteorites, so you are not far off at 
> all if
> we deal with CuSo4*5H20 !!
>
> However, the more common hydrated (i.e., bound water) reservoirs found  in
> some meteorites I found in the literature based on your contemplation of 
> not
> even guessing, would be a suite of clay minerals, which can result from 
> the
> aqueous modification ("weathering") products of feldspars and pyroxenes, 
> common
> meteoritic stock.  That is the same kinds of clay that expands when you 
> mix
> it with water and can be formed into shapes...i.e., hydrated clay - well 
> not
> all  Clays hydrate, but plenty do.
>
> Clay minerals are very complicated beasts  that still cause all kinds of
> trouble even regarding nomenclature to say what is  what, since their 
> structures
> vary so much, simply being a woven backbone pattern  of silicates and
> hydroxides and a variety of candidate cations/metals, and  ambiguous 
> formulae something
> like (Ca,Na,H)(Al,Mg,Fe,Zn)2(Si,Al)4O10(OH)2*n(H2O)  in the case of
> smectites, which can form widely variable laminar sheets which  suck up 
> water between
> them better than silica gel!  Unlike copper sulfate,  slight changes in
> temperature and humidity can reverberate by changing their  structures, 
> formula, and
> most importantly, amount of bound water - even getting  a density is hard, 
> let
> alone a positive compositional ID.  So that is why  you can't do too much
> better than "clay minerals".  The two best tests are  a taste test and 
> messy
> Separation-Xray analysis.  And that would seem to be  the 
> variable/flexible nature
> of much of the bound water in  not-too-shocked-and-baked meteoroids for 
> s/he
> who wants to really do some  bonding with them...
>
> For chondrites, here are some of those hydrated  beasts that serve as 
> space
> oasises (that has a nice ring to it):
>
> Type 3:  phyllosilicates, principally smectites and micas, serpentine
> associated with  ferrihydrite.
> Type 2: Smectites (rare in the CM2s, abundant in the CR2s),  Abundant
> serpentines (with extremely variable compositions and structures),  Mg-Fe 
> sulfates,
> tochilinite-serpentine intergrowths and carbonates.
> Type 1:  Saponite + (Serpentine)
>
> Taken from an impressive face-off of Zolensky  and Bischoff in Maui at:
> WORKSHOP ON PARENT-BODY AND NEBULAR MODIFICATION OF  CHONDRITIC MATERIALS
> (preliminary program)
> June 17, 1997, Maui,  Hawai'i
> http://www.lpi.usra.edu/meetings/chondrite/pdf/program.pdf
>
> I  chose the Zolensky writeup not because I don't believe the other 
> competing
> theories (I am a Bischoff fan), but rather because of the enumeration of
> minerals he did including some clay and other hydrate-ables.  The 
> documentation
> is:
> AQUEOUS ALTERATION OF CARBONACEOUS CHONDRITES: EVIDENCE FOR  ASTEROIDAL
> ALTERATION. M. E. Zolensky, Mail Code SN2, NASA Johnson Space  Center,
> Houston TX 77058, USA.
>
> Wish to have been a fly for three days on  the hotel wall in Maui then,
> Aloha, Doug
>
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