Wonderful new Martian meteorite Martin! It has been a while since a nice new Mars rock hit the market. I am still waiting for a large Martian meteorite fall, that will be a dream come true if that happens. Mike
--- Martin Altmann <[EMAIL PROTECTED]> wrote: > Dear Collectors, > > The presentation of a new Martian meteorite to the > meteorite community is > always an event. > Such introductions of new lunaites and Martians are > those moments that are > most fulfilling in the life and work of a > meteorite-addicted person. > And we hope that you will share at least partially > our exaltation about this > new fabulous stone, named > > NWA 4925 > Purchased 2007, > Morocco > Tkw 282.3g > o-SHE > > Understandably, we aren't really unbiased regarding > our new Mars rock, and > so we asked one of the best and most experienced > connoisseurs of Martian > meteorites, Norbert Classen, known also to be the > author of one of the best > homepages for lunar and Martian meteorites > (http://www.meteoris.de/) for his > opinion on NWA 4295, and we are much obliged that he > allowed us to report > his observations and his opinions about the new > material: > > "Right now we know about 50 different, i.e. unpaired > Martian meteorites, > including 4 witnessed falls (Chassigny, Shergotty, > Nakhla, and Zagami), 15 > Antarctic finds, and 31 hot desert finds, most of > them having been recovered > from the deserts of Africa. The majority of all > Martian meteorites belongs > to the class of mostly "enriched" basaltic > shergottites, while the > "depleted" group of olivine-phyric, and > olivine-orthopyroxene-phyric > shergottites are far less abundant. NWA 4925 belongs > to the latter subgroup > which consists of just about 5 different members, > including the Dar al Gani > shergottites, NWA 1195, NWA 2626, NWA 2046, and NWA > 4527 (TKW 10g). NWA 4925 > is possibly paired with the latter one, but up to > this moment no studies > have been conducted to prove or disprove this > suspicion that's only based on > a comparison of overall texture, and weathering > grade. > > Like NWA 1195 and NWA 4527, the new NWA 4925 > exhibits a pronounced light > colored weathering rind, typical for desert finds > with long terrestrial > residence ages. Olivine phenocrysts near to or > within the weathering rind do > often show a bright red appearance, a sign that most > of the iron within > these olivines has been oxidized in the terrestrial > environment. Overall, > the matrix color within or near to the rind is more > redish - reminding us of > the same process that gives Mars its red appearance > although most of the > Martian rocks are originally of grey, or grey to > green color. The interior > of NWA 4925 is actually dark green, with shock > altered dark-brown olivine > phenocrysts set in a matrix of more fine grained > greenish pyroxenes and dark > maskelynite, both bearing witness for the fact that > the interior of the rock > is more or less pristine and fresh, just as if it > left Mars only yesterday. > It's that interesting contrast of the more > light-colored weathering rind > with its neat redish olivines, and the dark-green, > very fresh interior that > makes NWA 4925 visually most attractive, and > scientifically interesting > because it models the surface weathering on the Red > Planet. > > >From the samples of NWA 4925 that I could study I > would further suspect that > the olivine and orthopyroxene phenocrysts show a > preferred orientation like > in NWA 1195, and other ol-opx-phyric shergottites, > something which is > indicative of magmatic flow prior to the cooling and > solidification of the > sample. Other most interesting features are melt > inclusions, and small > chromites that are enclosed into the large olivine > phenocrysts. Overall, a > very interesting, and optically most attractive new > Martian meteorite of a > rare class. A "must have" for any serious collector > of planetary meteorites, > and rare achondrites." > > > Dear collectors, > For us the acquisition of this new Martian was > combined with various > difficulties and we are glad and happy to have it > finally in our very hands. > Therefore we simply decided against all advice and > economical reason to > share our joy and to choose for this introductory & > exclusive special > > a price of 400$ per gram! > > We hope for your understanding, that this offer will > be limited for the > pieces pictured on the special-page and for all > other orders too (in case > the special-specimens will be sold out) until Sunday > next week; and that > afterwards we will have to adjust the price to the > more general Martian > price-level. > > And here is the beef: > > http://www.chladnis-heirs.com/special-nwa4925.html > > > Enjoy! > Martin & Stefan > > Chladni's Heirs > Munich - Berlin > Fine Meteorites for Science&Collectors > > > > ______________________________________________ > http://www.meteoritecentral.com > Meteorite-list mailing list > Meteorite-list@meteoritecentral.com > http://six.pairlist.net/mailman/listinfo/meteorite-list > ______________________________________________ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list