[meteorite-list] AD: Special: A New, unusual and Unbrecciated Aubrite! NWA 6350 prov

From: Chladnis Heirs <news_at_meteoritecentral.com>
Date: Wed, 13 Oct 2010 22:01:15 +0200
Message-ID: <008801cb6b11$64f3b3a0$2edb1ae0$_at_com>

Dear collectors and meteoricists,


after a long time, we are back with one of our Specials,
which became necessary, as this time we want to introduce a stone,
where it's difficult to avoid the so worn-out term: "Sensational".


NWA 6350 provisional - A new aubrite.


If you follow us, in checking the Meteoritical Bulletin database,
you'll understand, why this find has such a special meaning for us.

The database is still somewhat biased, as the numerous El Haggouina-pairings
there aren't changed from AUB to EL yet.
(And with them we personally follow Bunch, Wittke, Irving et al. that El
Haggouina is an EL).

So the first true aubrite in the list there, should be NWA 4799.
You remember, it was introduced here on the list, the very uncommon highly
brecciated one.
To what extent NWA 4832/4871 are belonging to NWA 4799, that we don't know
yet; David Weir lists 4871 as a pairing of NWA 4799

Find them here, also a wonderful resource of information, on the meteorite
pages of NAU:
http://www4.nau.edu/meteorite/Meteorite/Aubrite.html


For NWA 5419 zero information is available, therefore not yet clear in which
context it belongs.


Well, and the second real aubrite was NWA 5217.
NWA 6350 is paired to it.

Therefore, from 2 decades of desert hunt in Sahara and 1 decade in Oman,
we have so far most probably only two different aubrites at all.
And aubrites are the most difficult discipline, it seems much more easier to
find a lunaite or even a nakhlite.


Hence, we choose in the title several attributes:

"Unbrecciated" we wrote, to show, that it is not paired with NWA 4799.

"Fresh" we could have added,
not only because NWA 6350 is relatively well preserved, but to signal, that
it isn't just another El Hagg.

But why we said "New"?
NWA 5217 was a small stone of 40grams. It is listed in the Bulletin to be at
an Anonymous.
Never we saw it offered - with NWA 6350 for the first time this exciting
material will be available for the collector.


"Unusual":

NWA 6350/5217 as well as NWA 4799 are important finds.
They both are distinct from the other aubrites.

Let us simply quote from that short abstract:
http://www.lpi.usra.edu/meetings/metsoc2008/pdf/5309.pdf

"The high temperature igneous cumulate characteristics
of NWA 4799 and 5217 are unique among aubrites.
Moreover, the complex mineralogy of NWA 5217 is remarkable
and distinctive. Because these aubrites appear to be igneous cumulates
and not derived from shock melts, they likely formed in
a fairly large parent body rather than a small asteroid (such as
main belt E asteroids and the NEO E asteroid 3103 Eger [2])."


And now in medias res.

NWA 6350 was unfortunately also of a very small tkw. 50grams the stone only
had.

The number of available specimens is so limited, that by far we wouldn't be
able to satisfy the needs of even only our truest collectors and customers.
Therefore we decided to set all pieces here on the list,
for everyone allowing the chance to get one equally.

We hope you don't mind, that we made an exception and had let David Weir to
pick a specimen in advance,
because his fantastic Meteorite Studies are such an enormous service to the
meteorite world,
that we think, that he deserves all support to keep his studies complete.
And - science first - one of the partial endcuts is temporary on hold for an
institute.

Although, as a cumulate one, its relative freshness and its tiny tkw,
we kept the prices with 60-100$/g
still partially in the Pena Blanca Spring range.
That Norton County can be had cheaper, is explained, also to the historics
collector, well by this hilarious photo:
http://kuerzer.de/Aubpaz


Usually, whenever we announce a novelty of such a caliber,
quite a rush of emails comes over us.
It would be extremely helpful, if you would send us a ranking of the
specimens you desire,
to grant a fast and chronologically course.

Now - long enough we kept you on the tenterhooks.

Here they are:

http://www.chladnis-heirs.com/special-nwa6350.html



Let the games begin!

Stefan Ralew & Martin Altmann

Chladni's Heirs
Munich - Berlin
Fine Meteorites for Science & Collectors
http://www.chladnis-heirs.com
Received on Wed 13 Oct 2010 04:01:15 PM PDT