An Article In Meteorite-Times Magazine
by Tom Phillips
NWA 969 LL6/7
LL6/7 This thin section was loaned to me from Jeff Krosschell. He and his wife Malia are helping out with the sale of some of Adam Hupe's stock while he is moving. Jeff helped me get the NWA 5000 on my scope! This slide was among the most beautiful I have seen. I really obsessed with it!
This was a post to the Met List by Adam about NWA 969.
NWA969 LL6/7 Meteorite Containing Bottled Water?
Northwest Africa 969 is an extremely rare LL6/7 type chondrite with fluid trains found in June of 2001. What makes this chondrite so interesting is that it was first mistaken for a Brachinite. Its composition, ratios and 120 degree triple junctions appeared identical to that of Brachina. The few differences being sparse oriented intergrowths (interpreted as relic chondrules) chondrules and actual trains of fluid in the olivine. Only after exhaustive testing and oxygen isotopes was it determined to come from the LL chondrite parent body. More interesting is the way the fluid (water?) is trapped. It is contained in small round cavities in the olivine grains forming bubble trains, which can be observed with a microscope in thin section. We refer to this fluid as 4.5 billion year old bottled water. Although water has been found in a few other chondrites, it was contained in halite (salt) crystals not cavities in olivine making this a unique meteorite. For more information we have included the separate entry found
in the 88th Meteoritical Bulletin below:
Northwest Africa 969
Purchased 2001 June/October
A small stone was purchased from a Moroccan dealer by A. and G. Hupé (Hupé) in 2001 June, and subsequently seven more stones were purchased bringing the total weight to 463 g. Classification and mineralogy (A. Irving and S. Kuehner, UWS): Genomict breccia consisting of angular clasts in a finer grained matrix. Mostly olivine (Fa30, FeO/MnO = 57.7) exhibiting 120? grain junctions, with subordinate interstitial troilite and Fe-Ni metal (30% Ni), and accessory orthopyroxene (FeO/MnO = 37.6), chromite, chlorapatite, interstitial sodic feldspar (Ab85Or5), and fine-grained intergrowth patches (probably former melt or mesostasis). Silicate minerals contain trains of fluid inclusions. Rare relict chondrules are present. Oxygen isotopes (D. Rumble, CIWGL): analyses of two whole rock fragments by laser fluorination gave ?18O = +5.3 ? 0.1, ?17O = +4.0 ? 0.1, ?17O = +1.22 ? 0.03 per mil. Specimens: type specimen, 20 g, and three polished thin sections, UWS; main mass, Hupé.
This first set of images were taken at magnifications of 160X and then 400X. The change of color is from the rotation of the slide in cross polarized light.
Alan Ruben (UCLA) (You all know him!) was kind enough to look at this feature and offer his analysis of what is going on in the image.
"It is clear that the rock has been shocked and annealed. The smudgy trails of dark blebs are of metal and sulfide that were melted by shock and injected into fractures. The fractures healed during subsequent thermal metamorphism, probably the heat that was developed during the impact that caused the initial shock."
These images are taken with my new Nikon CoolPix camera at 8mp. Paul and Jeff are checking into what kind of prints we can make with this new resolution.
Here it is at a magnification of 63X.
Every material has a sweet spot for magnification level and this slide seemed to look best at 160X.
Looks like I found one of the chondrules Adam was talking about!!!
Finally I have a couple more taken at 400X.
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