[meteorite-list] primitive Ureilite ?
From: Adam Hupe <raremeteorites_at_meteoritecentral.com>
Date: Tue Sep 28 13:35:24 2004 Message-ID: <009601c4a580$575b1380$6401a8c0_at_c1720188a> Hi List, Matt is correct in stating that all Ureilites are primitive. The reason I used the word primitive in describing NWA 3140 is that it is less evolved than that of other Ureilites. It even has areas containing elemental metal, no differentiation between crystals/matrix and is relatively diamond poor. I enjoy Ureilites when prepared properly (by somebody else) because they are striking under magnification. I do not enjoy preparing them myself because it usually takes 30 times the effort to do it right because of the diamonds. NWA 3140 does not destroy blades and polishing pads during preparation making it a pleasure to work with. In the past we worked with a diamond-rich Ureilite called NWA 3135. To make a 2.8 centimeter cut cost us 3 blades, 2 diamond lap wheels and over 3 hours of effort making it a true nightmare. All the best, ------------------------------------ Adam Hupe The Hupe Collection Team LunarRock IMCA 2185 raremeteorites_at_comcast.net ----- Original Message ----- From: "Matt Morgan" <mmorgan_at_mhmeteorites.com> To: <j.divelbiss_at_att.net> Cc: <meteorite-list_at_meteoritecentral.com> Sent: Tuesday, September 28, 2004 9:59 AM Subject: RE: [meteorite-list] primitive Ureilite ? John: I am sure Adam will have something to add but here is a good description of Ureilites http://www.daviddarling.info/encyclopedia/U/ureilite.html I always thought that all ureilites were "primitive". So someone please enlighten us! Matt Morgan -----Original Message----- From: meteorite-list-bounces_at_meteoritecentral.com [mailto:meteorite-list-bounces_at_meteoritecentral.com] On Behalf Of j.divelbiss_at_att.net Sent: Tuesday, September 28, 2004 10:51 AM To: meteorite-list_at_meteoritecentral.com Subject: [meteorite-list] primitive Ureilite ? Hello all, I was reading one of Adam's auctions this morning and noticed the word primitive attached to the word Ureilite and began to wonder what was the latest status on Ureilites being considered "primitive". I know the word is used with primitive materials like Acapulcoites and Lodranites because their age is suggested at the chondrite level of 4.5+ billion years. I believe this reference for Ureilites infers the involvement of pre-solar or solar parts such as the diamonds versus a formation age of 4.5 billion years. Or maybe I'm wrong about that. At one time the diamonds were thought to be shock/pressure related, but recently Ureilites with low-shock values have been found that has scientists thinking that the diamonds came from some other source. What is considered the formation age of Ureilites? And does that age in itself make them primitive, or does the parts/pieces make them considered primitive? Curious, John/JD ______________________________________________ Meteorite-list mailing list Meteorite-list_at_meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list ______________________________________________ Meteorite-list mailing list Meteorite-list_at_meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list Received on Tue 28 Sep 2004 01:26:50 PM PDT |
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