[meteorite-list] AD: Special: NWA 6659 prov. - Superior Lodranite

From: Chladnis Heirs <news_at_meteoritecentral.com>
Date: Wed, 16 Nov 2011 19:20:22 +0100
Message-ID: <008201cca48c$67ad9e70$3708db50$_at_com>

Dear meteorite friends,


in our weekly Special we're able this time to present you a wonderful
dainty: NWA 6659 - a Lodranite!

Lodranites are counted among the absolutely rarest classes a meteorite
collector can have in his cabinet and a meteoricist in his lab.
Currently the Meteorite Bulletin Database accounts for only 32 lodranitic
numbers with a combined weight of 9.39kg (15 of them with 1.14kg yielded the
Antarctic campaigns of the last 35 years). And 9 numbers not otherwise
specified as belonging to the acapulcoite-lodranite family with 0.33kg
(7 Antarctics) - making the lodranites to a much rarer type than any lunar
meteorite.

Let us say as long-time established meteorite offerers, that it was the
NWA-complex of the recent decade, which brought the lodranites at all in the
range of the collector and a certain variety of finds into the research
institutes. A check of our global price compilation of the season ten years
ago only (660 different meteorites, 92 offerers - currently available in the
German meteorite forum), gives, that the only chance to get a lodranite was
then to acquire micromounts of Lodran, priced at an average of 38,400$ a
gram and that among the related acapulcoites, the collector had only the
choice between Acapulco (average 1408$/g) and Monument Draw (1016$/g).

Lodranites and acapulcoites share common ground and are generic relatives
from the same parent body, which seems to have had consisted of a CM or
CI-like precursor material. The main differences between these types is the
lack of plagioclase in the lodranites and the larger grain-sizes than the
acapulcoites display, hence indicating that lodranites underwent during
their melt phase higher temperatures and a different cooling period,
stemming from deeper layers than the acapulcoites.
However, as enigmatic that group perhaps still might be - it are just the
very recent years with these new desert finds, which lead science to develop
a better understanding of the composition and the complex thermal history of
the acapulcoite-lodranite parent body.
A perfect overview of the brand-new models and hypotheses you will find on
David Weir's meteorite studies pages.

The perhaps a little provocative title of this Special we chose, because
most lodranitic specimens in our collections are recruited from the large
pairing group, which was revised from ACAP to LOD and where we once all
tried to put the numbers together here on the list (NWA 2565/2714/2866
seqq.)
And we regard NWA 6659 as definitely more comely.
It is better preserved than the old group, which had weathering grades of W3
and W3-4.
Not only the crystals of NWA 6659 are still relatively fresh-looking - it
has even here and there some metal grains and of course:
Yes - the so highly desired Triple Junctions superabound.

All slices were grinded and polished successively with 6 different grits;
and you find them here:

http://www.chladnis-heirs.com/specials/special-nwa6659.html


Regarding the statistics from above, keeping in mind, that the Great Desert
Area is coming to an end and emphasizing that we price NWA 6659 at the
lowest edge of the lodranite spectrum, we think, that these specimens are
not only of highest interest for the advanced collector, but would
wholeheartedly commend them as an excellent choice also for the beginning
meteorite enthusiast, as one-and-only specimen for having an perfect
representative, once and for all, of that fascinating and so exceedingly
rare class.


Best regards,
Stefan & Martin

Chladni's Heirs
Munich - Berlin
Fine Meteorites for Science & Collectors

http://www.chladnis-heirs.com
Received on Wed 16 Nov 2011 01:20:22 PM PST