[meteorite-list] Greg Hupé's gorgeous NWA 4883 eucrite ...

From: bernd.pauli at paulinet.de <bernd.pauli_at_meteoritecentral.com>
Date: 20 Dec 2007 13:36:22 UT
Message-ID: <DIIE.000000AB000023DE_at_paulinet.de>

.. 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
Received on Thu 20 Dec 2007 08:36:22 AM PST