[meteorite-list] Greg Hupé's gorgeous NWA 4883 eucrite ...
From: jbaxter112 at pol.net <jbaxter112_at_meteoritecentral.com>
Date: Thu, 20 Dec 2007 09:25:32 -0500 (EST) Message-ID: <31149.10.250.10.1.1198160732.squirrel_at_webmail.medscape.com> I second Berndt's opinion. I have never seen a eucrite like this. My slice also captivated me under the microscope-amazing complexity and variety! Easily an order of magnitude more beautiful under the microscope than any other eucrite I've seen. Jim Baxter > .. arrived today and I must tell you that it is out-of-this-world! My > 11.9-gram endcut can keep you busy for hours!!! Its dark-brown crust > still shows traces of black, glossy fusion crust and the abundant > colorless, pale bluish or even pale greenish but *limpid* maskelynite > crystals clearly testify to its intense shock history. > > This complex, polymict eucrite breccia shows all kinds of clasts but the > most exotic feature of my endcut is what only two of the pieces showed > and what Stefan Brandes so aptly described as a "cosmic spider web": > > These elongated, acicular (augite?) crystals have an average length of > 0.7 mm but some are longer than 1 mm and some are arranged in a > star-like pattern with up to nine or ten elongate crystals radiating > from a central point or "nucleus". > > Troilite is present in some places and this endcut also sports a > medium-gray angular, lithic clast measuring a whopping 5.5 mm in longest > dimension. Under the microscope it is "marbly" in appearance. > > Furthermore there are a few tiny specks of (Ni-free) metal and another > oddity is this: > > One translucent maskelynite crystal measuring 0.9 mm contains numerous, > milky-white very small (length ca. 0.05 mm) worm-like features (almost > like rice grains) that are reminiscent of air bubbles caught in frozen > water while trying to ascend to the surface! > > What a meteorite! > > Take care, > > Bernd > > > ______________________________________________ > http://www.meteoritecentral.com > Meteorite-list mailing list > Meteorite-list at meteoritecentral.com > http://six.pairlist.net/mailman/listinfo/meteorite-list Received on Thu 20 Dec 2007 09:25:32 AM PST |
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