Re: [meteorite-list] Predynastic LDG tools
On Tue, 1 Oct 2002 18:45:25 EDT, [EMAIL PROTECTED] wrote: To List: Does anybody know of a good reference (preferably a web site) that discusses stone tools made from Libyan Desert Glass (i.e. most common occurrences, tool types, etc..)? Hello Randy and list, there is quite some reference material regarding prehistoric artifacts recovered from the sahara deserts. I did not yet step over a website covering your particular subject but the following publications refer to LDG, standard tool types as well as to the other materials that have been used. If you roughly know what period your tools belong to (paleo-, epipaleo- or neolithic) classification is indeed much easier. You may as well have a look at the prehistoric finds inventory at our website: http://www.niger-meteorite-recon.de/praehist.htm The classifications are also in english, so some of it may be of use for you. In march 03 we recovered some 120 artifacts, about 20% are already listed in the inventory catalogue. This is a rich article about LDG tools recovered from the Great Sand Sea in the one and only Bullettin for Archaeoastronomy: Carlson, John B., ed., Archaeoastronomy: The Bulletin of the Center for Archaeoastronomy, Volume V, no. 2, April-June 1982. Olsen, John W., ``Libyan Desert Glas and the Prehistory of the Great Sand Sea,'' p. 11. The paleolithics are best covered by: Francois Bordes: Lecons sur le Paleolithique, Vol II, Paris 1984. This is probably the most suitable tool for your research because it covers most of the published finds in all Northafrica until the 1980s. Each entry goes along with various sources for futher research. Alphabetical order allows to search either for special tool types or for the location your tools have been found at: Andre Léroi-Gourhan: Dictionaire de la prehistoire, foreword by José Garanger, Paris 1986 This is a German standard refernce guide for recognition and classification of prehistoric tools: Hansjuergen Mueller Beck (ed.): Erkennen und Bestimmen von Stein und Knochenartefakten, Tuebingen 1993. With an online dictionary classifications can easyly be translated. At: http://www.oxbowbooks.com/browse.cfm?CatID=360StartRow=11 you will find an english research report of the Olduvai excavation in Northern Tansania. It contains a complete tool inventory of the average Atérien hunter clan and is also representative for the Atérien in Libya resp. the northeastern Africa. If somebody else comes aross any reference website I would be thankful for a link as well. best wishes Svend __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] October Issue of METEORITE TIMES
Hi Paul all, Thanks to Paul Jim for their ceaseless efforts in bringing us this fine publication. I had a number of additional photos from the Denver Show that didn't make it into the report on the show in my column and will have a link sent to the list forthwith. (apologies to whodat)) Best wishes, Michael on 10/1/02 10:52 PM, Paul Harris at [EMAIL PROTECTED] wrote: Dear List, The October Issue of MeteoriteTimes ready to view at: http://www.meteoritetimes.com/ Happy Reading! Paul and Jim Paul Harris [EMAIL PROTECTED] Jim Tobin [EMAIL PROTECTED] The Meteorite Exchange, Inc. http://www.meteorite.com MeteoriteTimes.com Magazine http://www.meteoritetimes.com PMB#455 P.O. Box 7000, Redondo Beach, CA 90277 USA FAX Number(310) 316-1032 __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list I don't give a damn for a man that can only spell a word one way. Mark Twain -- Worth Seeing: - Earth at night from satelite: http://antwrp.gsfc.nasa.gov/apod/image/0011/earthlights_dmsp_big.jpg -Earth - variety of choices: http://www.fourmilab.ch/earthview/vplanet.html -- COLLEGE MONEY CLICK HERE to search 600,000 scholarships! http://us.click.yahoo.com/iZp8OC/4m7CAA/ySSFAA/jFYolB/TM -- Michael Blood Meteorites Didgeridoos for sale at: http://www.michaelbloodmeteorites.com/ __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] October Issue Is Up!
Hi all, Here are the other Denver Show Photos: http://community.webshots.com/album/51497239BHkcYz Best wishes, Michael on 10/1/02 10:52 PM, Paul Harris at [EMAIL PROTECTED] wrote: Dear List, The October Issue of MeteoriteTimes ready to view at: http://www.meteoritetimes.com/ Happy Reading! Paul and Jim Paul Harris [EMAIL PROTECTED] Jim Tobin [EMAIL PROTECTED] The Meteorite Exchange, Inc. http://www.meteorite.com MeteoriteTimes.com Magazine http://www.meteoritetimes.com PMB#455 P.O. Box 7000, Redondo Beach, CA 90277 USA FAX Number(310) 316-1032 __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list I don't give a damn for a man that can only spell a word one way. Mark Twain -- Worth Seeing: - Earth at night from satelite: http://antwrp.gsfc.nasa.gov/apod/image/0011/earthlights_dmsp_big.jpg -Earth - variety of choices: http://www.fourmilab.ch/earthview/vplanet.html -- COLLEGE MONEY CLICK HERE to search 600,000 scholarships! http://us.click.yahoo.com/iZp8OC/4m7CAA/ySSFAA/jFYolB/TM -- Michael Blood Meteorites Didgeridoos for sale at: http://www.michaelbloodmeteorites.com/ __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] question: Tafassasset classification
Hello Anne and list, Sinve I recovered a small fragment from the Tafassasset strewfield I have a few questions regarding the current research on this meteorite. Our 9g Individual has been classified as carbonaceous chondrite or primitive achondrite (equilibrated CR-like meteorite). A quite exotic classification that in terms of nomenclature refers to the entry in MAPS 37 (provisional announcement, p.19f.). In other papers Tafassasset is usually discussed as equilibrated CR-chondrite or CR-like chondrite or sometimes as ungrouped CR-chondrite. J. Zipfel from the MPI in Mainz says that refractory lithophiles fractionated compared to a typical CR composition is leading to a possible classification as primitive achondrite. Does anybody know about a final classification yet? Second question is TKW. In the first report in MAPS 37 the TKW is discribed as 110kg. But I just came across an article by Anne Black in Fusion Crust (march 02). (You should see the outstanding Tafassasset specimen on her page!) She reports about recent analysis and the fact, that some of the material recovered in fact turned out to be meteorites of other petrologic types. As I intend to put an endcut of my recovered individual on ebay any information about TKW and final classification would be aprecciated. Concerning colour and texture of Tafassasset I was surprised to see that other specimen show a grey or light grey matrix. Except for the many kamacite and martensite grains mine shows a dark almost black matrix. If anybody in the list knows similar Tafassasset samples I would be thankful for a post. thanks all for your efforts best wishes Svend www.niger-meteorite-recon.de http://www.niger-meteorite-recon.de prospection expedition services, research permissions, topographic and geomorphological data IMCA member # 6540 __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Tafassasset classification
Svend wrote: J. Zipfel from the MPI in Mainz says that refractory lithophiles fractionated compared to a typical CR composition is leading to a possible classification as primitive achondrite. Does anybody know about a final classification yet? Hello Anne, Svend and List, In the Abstract issue of MAPS (vol. 37-7, July 2002, p. A155), Jutta Zipfel et al. published an abstract re: Tafassasset. In the discussion part, the authors state: The figure illustrates that both samples have compositions clearly fractionated from CI and other chondrite groups. Tafassasset has AI/Mg and Mn/Mg ratios similar to other primitve achondrites, indicating incipient partial melting involving mobilization of SiO2 (+/- A1203, CaO, etc.) -, P205- and S-rich melts. Although the bulk compositions are heterogeneous, characteristic element signatures (e.g., low Zn, Mn/Mg,depletion in refractory lithophile elements) e x c l u d e a relationship to CR chondrites and support pairing of Taf-Pa and Taf-Frei*. * Taf-Pa is the Paris material - Taf-Frei the Freiburg material Cheers, Bernd __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Michael's Who is it Photo
Hello Michael and list, The person in the unidentified photos in Michael Blood's Denver photos in Donald Hahn. Some of you may know him as he sells books, and carries a large inventory of meteorite books. Thanks, Mark Bostick
Re: AW: [meteorite-list] Tafassasset classification
Hello all Another paired is probably Grein 004 Regards Matteo --- Norbert Classen [EMAIL PROTECTED] wrote: Hello Bernd, Svend, Anne, and List, I discussed this subject several times with my old friend Dr. Otto, the German researcher who did the original analysis on Tafassasset (Freiburg), a stone that was originally submitted to the NomCom. as Tenere 001, a new ungrouped primitive achondrite similar to Divnoe, and the brachinites. He was more than suprised that the paired Tafassasset (Paris) has been submitted as an equilibrated CR chondrite. He gave me several reasons for his original classification of Taf- Frei as a primitive achondrite, but I can't remember them all right now (you know, I don't have a degree in mineralogy, petrology, and/ or cosmochemistry). But I remember his central argument: primitive achondrites show a more or less completely recrystallized matrix that looks entirely different from even highly equilibrated chondrites. He showed me several thin sections of various PACs, and equilibrated chondrites, and in fact, Tafassasset closely resembles other primitive achondrites, such as Divnoe, Reid 027, and Zag (b). No equilibrated chondrite has such a coarse grained matrix, which is a typical sign for recrystallization (if I got Dr. Otto right). There were other points in Dr. Otto's argumentation that convinced me of his point of view, and his view is obviously backed up by the research that Dr. Zipfel et al performed on Tafassasset, more recently. Obviously, there is some resistance to accept the fact that this nice meteorite is no extraordinary CR - something that has to do with the self importance of certain scientists that made extraordinary claims, but failed to provide extraordinary proofs. Just my two Tafs, Norbert -Original Message- Svend wrote: J. Zipfel from the MPI in Mainz says that refractory lithophiles fractionated compared to a typical CR composition is leading to a possible classification as primitive achondrite. Does anybody know about a final classification yet? Hello Anne, Svend and List, In the Abstract issue of MAPS (vol. 37-7, July 2002, p. A155), Jutta Zipfel et al. published an abstract re: Tafassasset. In the discussion part, the authors state: The figure illustrates that both samples have compositions clearly fractionated from CI and other chondrite groups. Tafassasset has AI/Mg and Mn/Mg ratios similar to other primitve achondrites, indicating incipient partial melting involving mobilization of SiO2 (+/- A1203, CaO, etc.) -, P205- and S-rich melts. Although the bulk compositions are heterogeneous, characteristic element signatures (e.g., low Zn, Mn/Mg,depletion in refractory lithophile elements) e x c l u d e a relationship to CR chondrites and support pairing of Taf-Pa and Taf-Frei*. * Taf-Pa is the Paris material - Taf-Frei the Freiburg material Cheers, Bernd __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list = M come Meteorite - Matteo Chinellato Via Triestina 126/A - 30030 - TESSERA, VENEZIA, ITALY Email: [EMAIL PROTECTED] Sale Site: http://www.mcomemeteorite.com Collection Site: http://www.mcomemeteorite.info International Meteorite Collectors Association #2140 MSN Messanger: [EMAIL PROTECTED] EBAY.COM:http:[EMAIL PROTECTED]/ __ Do you Yahoo!? New DSL Internet Access from SBC Yahoo! http://sbc.yahoo.com __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Att: LIST MODERATOR
Hi list, Tolist moderator , For some reason I am not aware of I am not receiving the lists email anymore. The list email stopped two days ago, Please check this out and see what the problem is ! Thanks , Best Regards, Steven Drummond"The Unknown Collector"
AW: AW: [meteorite-list] Tafassasset classification
Hi Matteo, hi List, Grein 004 as well as Tenere 001 are just synonyms for the Tafassasset Freiburg mass, a single stone weighing 3610 grams. It's no pairing. Just to avoid further confusion... Best, Norbert -Original Message- Hello all Another paired is probably Grein 004 Regards Matteo --- Norbert Classen [EMAIL PROTECTED] wrote: Hello Bernd, Svend, Anne, and List, I discussed this subject several times with my old friend Dr. Otto, the German researcher who did the original analysis on Tafassasset (Freiburg), a stone that was originally submitted to the NomCom. as Tenere 001, a new ungrouped primitive achondrite similar to Divnoe, and the brachinites. He was more than suprised that the paired Tafassasset (Paris) has been submitted as an equilibrated CR chondrite. He gave me several reasons for his original classification of Taf- Frei as a primitive achondrite, but I can't remember them all right now (you know, I don't have a degree in mineralogy, petrology, and/ or cosmochemistry). But I remember his central argument: primitive achondrites show a more or less completely recrystallized matrix that looks entirely different from even highly equilibrated chondrites. He showed me several thin sections of various PACs, and equilibrated chondrites, and in fact, Tafassasset closely resembles other primitive achondrites, such as Divnoe, Reid 027, and Zag (b). No equilibrated chondrite has such a coarse grained matrix, which is a typical sign for recrystallization (if I got Dr. Otto right). There were other points in Dr. Otto's argumentation that convinced me of his point of view, and his view is obviously backed up by the research that Dr. Zipfel et al performed on Tafassasset, more recently. Obviously, there is some resistance to accept the fact that this nice meteorite is no extraordinary CR - something that has to do with the self importance of certain scientists that made extraordinary claims, but failed to provide extraordinary proofs. Just my two Tafs, Norbert -Original Message- Svend wrote: J. Zipfel from the MPI in Mainz says that refractory lithophiles fractionated compared to a typical CR composition is leading to a possible classification as primitive achondrite. Does anybody know about a final classification yet? Hello Anne, Svend and List, In the Abstract issue of MAPS (vol. 37-7, July 2002, p. A155), Jutta Zipfel et al. published an abstract re: Tafassasset. In the discussion part, the authors state: The figure illustrates that both samples have compositions clearly fractionated from CI and other chondrite groups. Tafassasset has AI/Mg and Mn/Mg ratios similar to other primitve achondrites, indicating incipient partial melting involving mobilization of SiO2 (+/- A1203, CaO, etc.) -, P205- and S-rich melts. Although the bulk compositions are heterogeneous, characteristic element signatures (e.g., low Zn, Mn/Mg,depletion in refractory lithophile elements) e x c l u d e a relationship to CR chondrites and support pairing of Taf-Pa and Taf-Frei*. * Taf-Pa is the Paris material - Taf-Frei the Freiburg material Cheers, Bernd __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list = M come Meteorite - Matteo Chinellato Via Triestina 126/A - 30030 - TESSERA, VENEZIA, ITALY Email: [EMAIL PROTECTED] Sale Site: http://www.mcomemeteorite.com Collection Site: http://www.mcomemeteorite.info International Meteorite Collectors Association #2140 MSN Messanger: [EMAIL PROTECTED] EBAY.COM:http:[EMAIL PROTECTED]/ __ Do you Yahoo!? New DSL Internet Access from SBC Yahoo! http://sbc.yahoo.com __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] white inclusions
I bought a nice NWA from Dean Bessey and it has white inclusions, a slightly off white, but white. What could these be? Thanks, Tom The proudest member of the I.M.C.A. #6168 Chat with friends online, try MSN Messenger: Click Here __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Tafassasset classification
Hello All, Primitive is primitive!Help me to understand the differences please. Is the argument about where the line(s) should be drawn between a chondrite (that is really differentiated...like a 7) versus a primitive achondrite (that is not quite differentiated enough to be called a achondrite)? Is there really a 7 category and why? Are primitive achondrites now considered differentiated enough to be distinguished from a highly changed chondrite? small versus coarse grains in matrix? How is this line drawn? mineral makeup, level of glass, age, grain size/changes, etc. ? Lots of questions with this story. Alain would have something to say about all this. Ann Black, is there a position written from his corner? John - Original Message - From: Norbert Classen [EMAIL PROTECTED] To: Bernd Pauli HD [EMAIL PROTECTED]; Svend Buhl [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Sent: Wednesday, October 02, 2002 2:30 PM Subject: AW: [meteorite-list] Tafassasset classification Hello Bernd, Svend, Anne, and List, I discussed this subject several times with my old friend Dr. Otto, the German researcher who did the original analysis on Tafassasset (Freiburg), a stone that was originally submitted to the NomCom. as Tenere 001, a new ungrouped primitive achondrite similar to Divnoe, and the brachinites. He was more than suprised that the paired Tafassasset (Paris) has been submitted as an equilibrated CR chondrite. He gave me several reasons for his original classification of Taf- Frei as a primitive achondrite, but I can't remember them all right now (you know, I don't have a degree in mineralogy, petrology, and/ or cosmochemistry). But I remember his central argument: primitive achondrites show a more or less completely recrystallized matrix that looks entirely different from even highly equilibrated chondrites. He showed me several thin sections of various PACs, and equilibrated chondrites, and in fact, Tafassasset closely resembles other primitive achondrites, such as Divnoe, Reid 027, and Zag (b). No equilibrated chondrite has such a coarse grained matrix, which is a typical sign for recrystallization (if I got Dr. Otto right). There were other points in Dr. Otto's argumentation that convinced me of his point of view, and his view is obviously backed up by the research that Dr. Zipfel et al performed on Tafassasset, more recently. Obviously, there is some resistance to accept the fact that this nice meteorite is no extraordinary CR - something that has to do with the self importance of certain scientists that made extraordinary claims, but failed to provide extraordinary proofs. Just my two Tafs, Norbert -Original Message- Svend wrote: J. Zipfel from the MPI in Mainz says that refractory lithophiles fractionated compared to a typical CR composition is leading to a possible classification as primitive achondrite. Does anybody know about a final classification yet? Hello Anne, Svend and List, In the Abstract issue of MAPS (vol. 37-7, July 2002, p. A155), Jutta Zipfel et al. published an abstract re: Tafassasset. In the discussion part, the authors state: The figure illustrates that both samples have compositions clearly fractionated from CI and other chondrite groups. Tafassasset has AI/Mg and Mn/Mg ratios similar to other primitve achondrites, indicating incipient partial melting involving mobilization of SiO2 (+/- A1203, CaO, etc.) -, P205- and S-rich melts. Although the bulk compositions are heterogeneous, characteristic element signatures (e.g., low Zn, Mn/Mg,depletion in refractory lithophile elements) e x c l u d e a relationship to CR chondrites and support pairing of Taf-Pa and Taf-Frei*. * Taf-Pa is the Paris material - Taf-Frei the Freiburg material Cheers, Bernd __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Holy Anvil shoot
Dear List; I see on TNN that a group conducts an anvil shoot contest. Seems this had been popular since the 1820's or even earlier. Contestants load a cannon of sorts with black powder and launch a 102 pound anvil skyward. One demonstrated shoot sent the anvil 563 feet up. Here's the fascinating part..102 pound anvil falling back down from 563 feet went into the hay field earth.3 feet deep! Now I know why I find no Wyoming meteorites, I need to be looking in hay fields for 3 feet deep holes! The show was very entertaining. Best, Dave Freeman __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] white inclusions
The most common white inclusion you will find in meteorites is a CAI, or calcium-aluminum inclusion. Allende meteorites are notorious for being chock-full of them. They are some of the first things that (theoretically) crystallize out of the proto-stellar dust cloud, and are regarded as being good indicators of what things were like way back then. Tracy Latimer On Wed, 2 Oct 2002, Tom / james Knudson wrote: I bought a nice NWA from Dean Bessey and it has white inclusions, a slightly off white, but white. What could these be? Thanks, Tom The proudest member of the I.M.C.A. #6168 __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] question: Tafassasset classification
In a message dated 10/2/2002 10:32:55 AM Mountain Daylight Time, [EMAIL PROTECTED] writes: Second question is TKW. In the first report in MAPS 37 the TKW is discribed as 110kg. But I just came across an article by Anne Black in Fusion Crust (march 02). (You should see the outstanding Tafassasset specimen on her page!) She reports about recent analysis and the fact, that some of the material recovered in fact turned out to be meteorites of other petrologic types. Thank you very much Svend!! I have many more pieces if anyone is interested. :-) As far as I know the TKW is still at best uncertain. I have copies of 2 reports on the composition of Tafassasset. One from the Musee d'Histoire Naturelle in Paris, and the other from the Max Planck Institute. Both classify Tafassasset as a Carbonaceous Chondrite, Renazzo-type, with relict chondrules. I also have some thin-sections of Tafassasset, if you would like to study it and decide for yourself. :-) Let me know! Anne Black IMCA #2356 www.IMPACTIKA.com e-mail: [EMAIL PROTECTED]
[meteorite-list] Ugliest Gibeon?
Greetings All: This has got to be the ugliest Gibeon I have ever seen: METEORITE 74lb. 33300gr. GIBEON. namibia RARE Item # 718994851 (If it is Gibeon, then it was adopted and raised by a family of Nantans ;>) Perhaps we should have "The Ugliest Meteorite Contest?" Best, ken newton BTW- Do any of the computer geniuses on List know why the List emails are failing to reach all __ @earthlink.net subscribers?
Re: [meteorite-list] Ugliest Gibeon?
Not that ugly. The picture does not do the meteorite justice. I am sure with some TLC this would be a fine meteorite. At that price, however, I would sure as heck get some good references to ensure that this was a Gibeon. Cheers, Mike Tettenborn, Owen Sound, Ontario - Original Message - From: magellon To: [EMAIL PROTECTED] Sent: Wednesday, October 02, 2002 9:50 PM Subject: [meteorite-list] Ugliest Gibeon? Greetings All: This has got to be the ugliest Gibeon I have ever seen: METEORITE 74lb. 33300gr. GIBEON. namibia RARE Item # 718994851 (If it is Gibeon, then it was adopted and raised by a family of Nantans ;) Perhaps we should have "The Ugliest Meteorite Contest?" Best, ken newton BTW- Do any of the computer geniuses on List know why the List emails are failing to reach all __ @earthlink.net subscribers?
Re: [meteorite-list] Tafassasset classification
Hello John and all, Regarding your primative achondrite question, Norton's Encyclopedia of Meteorites has a page dedicated to the subject (P. 165). He states that primative achondrites have achondrite textures but still retain something of their chondritic composition. and that they are transitional between chondrites and achondrites. As examples of primative achondrites, he uses acapulcoites, lodranites and winonaites. Hope this helps. Frank - Original Message - From: John Divelbiss [EMAIL PROTECTED] To: Norbert Classen [EMAIL PROTECTED]; Bernd Pauli HD [EMAIL PROTECTED]; Svend Buhl [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Sent: Wednesday, October 02, 2002 5:05 PM Subject: Re: [meteorite-list] Tafassasset classification Hello All, Primitive is primitive!Help me to understand the differences please. Is the argument about where the line(s) should be drawn between a chondrite (that is really differentiated...like a 7) versus a primitive achondrite (that is not quite differentiated enough to be called a achondrite)? Is there really a 7 category and why? Are primitive achondrites now considered differentiated enough to be distinguished from a highly changed chondrite? small versus coarse grains in matrix? How is this line drawn? mineral makeup, level of glass, age, grain size/changes, etc. ? Lots of questions with this story. Alain would have something to say about all this. Ann Black, is there a position written from his corner? John - Original Message - From: Norbert Classen [EMAIL PROTECTED] To: Bernd Pauli HD [EMAIL PROTECTED]; Svend Buhl [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Sent: Wednesday, October 02, 2002 2:30 PM Subject: AW: [meteorite-list] Tafassasset classification Hello Bernd, Svend, Anne, and List, I discussed this subject several times with my old friend Dr. Otto, the German researcher who did the original analysis on Tafassasset (Freiburg), a stone that was originally submitted to the NomCom. as Tenere 001, a new ungrouped primitive achondrite similar to Divnoe, and the brachinites. He was more than suprised that the paired Tafassasset (Paris) has been submitted as an equilibrated CR chondrite. He gave me several reasons for his original classification of Taf- Frei as a primitive achondrite, but I can't remember them all right now (you know, I don't have a degree in mineralogy, petrology, and/ or cosmochemistry). But I remember his central argument: primitive achondrites show a more or less completely recrystallized matrix that looks entirely different from even highly equilibrated chondrites. He showed me several thin sections of various PACs, and equilibrated chondrites, and in fact, Tafassasset closely resembles other primitive achondrites, such as Divnoe, Reid 027, and Zag (b). No equilibrated chondrite has such a coarse grained matrix, which is a typical sign for recrystallization (if I got Dr. Otto right). There were other points in Dr. Otto's argumentation that convinced me of his point of view, and his view is obviously backed up by the research that Dr. Zipfel et al performed on Tafassasset, more recently. Obviously, there is some resistance to accept the fact that this nice meteorite is no extraordinary CR - something that has to do with the self importance of certain scientists that made extraordinary claims, but failed to provide extraordinary proofs. Just my two Tafs, Norbert -Original Message- Svend wrote: J. Zipfel from the MPI in Mainz says that refractory lithophiles fractionated compared to a typical CR composition is leading to a possible classification as primitive achondrite. Does anybody know about a final classification yet? Hello Anne, Svend and List, In the Abstract issue of MAPS (vol. 37-7, July 2002, p. A155), Jutta Zipfel et al. published an abstract re: Tafassasset. In the discussion part, the authors state: The figure illustrates that both samples have compositions clearly fractionated from CI and other chondrite groups. Tafassasset has AI/Mg and Mn/Mg ratios similar to other primitve achondrites, indicating incipient partial melting involving mobilization of SiO2 (+/- A1203, CaO, etc.) -, P205- and S-rich melts. Although the bulk compositions are heterogeneous, characteristic element signatures (e.g., low Zn, Mn/Mg,depletion in refractory lithophile elements) e x c l u d e a relationship to CR chondrites and support pairing of Taf-Pa and Taf-Frei*. * Taf-Pa is the Paris material - Taf-Frei the Freiburg material Cheers, Bernd __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list __ Meteorite-list mailing list [EMAIL PROTECTED]
Re: [meteorite-list] Tafassasset classification
Frank, I understand the description of the primitive achondrite...including the types you mention. From that statement in Nortons book, they are still chondrites...just overdone a bit. What line did they cross to be called achondrites? And how does it relate to Tafassasset being also called a CR7? John - Original Message - From: fcressy [EMAIL PROTECTED] To: John Divelbiss [EMAIL PROTECTED]; Norbert Classen [EMAIL PROTECTED]; Bernd Pauli HD [EMAIL PROTECTED]; Svend Buhl [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Sent: Wednesday, October 02, 2002 10:55 PM Subject: Re: [meteorite-list] Tafassasset classification Hello John and all, Regarding your primative achondrite question, Norton's Encyclopedia of Meteorites has a page dedicated to the subject (P. 165). He states that primative achondrites have achondrite textures but still retain something of their chondritic composition. and that they are transitional between chondrites and achondrites. As examples of primative achondrites, he uses acapulcoites, lodranites and winonaites. Hope this helps. Frank - Original Message - From: John Divelbiss [EMAIL PROTECTED] To: Norbert Classen [EMAIL PROTECTED]; Bernd Pauli HD [EMAIL PROTECTED]; Svend Buhl [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Sent: Wednesday, October 02, 2002 5:05 PM Subject: Re: [meteorite-list] Tafassasset classification Hello All, Primitive is primitive!Help me to understand the differences please. Is the argument about where the line(s) should be drawn between a chondrite (that is really differentiated...like a 7) versus a primitive achondrite (that is not quite differentiated enough to be called a achondrite)? Is there really a 7 category and why? Are primitive achondrites now considered differentiated enough to be distinguished from a highly changed chondrite? small versus coarse grains in matrix? How is this line drawn? mineral makeup, level of glass, age, grain size/changes, etc. ? Lots of questions with this story. Alain would have something to say about all this. Ann Black, is there a position written from his corner? John - Original Message - From: Norbert Classen [EMAIL PROTECTED] To: Bernd Pauli HD [EMAIL PROTECTED]; Svend Buhl [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Sent: Wednesday, October 02, 2002 2:30 PM Subject: AW: [meteorite-list] Tafassasset classification Hello Bernd, Svend, Anne, and List, I discussed this subject several times with my old friend Dr. Otto, the German researcher who did the original analysis on Tafassasset (Freiburg), a stone that was originally submitted to the NomCom. as Tenere 001, a new ungrouped primitive achondrite similar to Divnoe, and the brachinites. He was more than suprised that the paired Tafassasset (Paris) has been submitted as an equilibrated CR chondrite. He gave me several reasons for his original classification of Taf- Frei as a primitive achondrite, but I can't remember them all right now (you know, I don't have a degree in mineralogy, petrology, and/ or cosmochemistry). But I remember his central argument: primitive achondrites show a more or less completely recrystallized matrix that looks entirely different from even highly equilibrated chondrites. He showed me several thin sections of various PACs, and equilibrated chondrites, and in fact, Tafassasset closely resembles other primitive achondrites, such as Divnoe, Reid 027, and Zag (b). No equilibrated chondrite has such a coarse grained matrix, which is a typical sign for recrystallization (if I got Dr. Otto right). There were other points in Dr. Otto's argumentation that convinced me of his point of view, and his view is obviously backed up by the research that Dr. Zipfel et al performed on Tafassasset, more recently. Obviously, there is some resistance to accept the fact that this nice meteorite is no extraordinary CR - something that has to do with the self importance of certain scientists that made extraordinary claims, but failed to provide extraordinary proofs. Just my two Tafs, Norbert -Original Message- Svend wrote: J. Zipfel from the MPI in Mainz says that refractory lithophiles fractionated compared to a typical CR composition is leading to a possible classification as primitive achondrite. Does anybody know about a final classification yet? Hello Anne, Svend and List, In the Abstract issue of MAPS (vol. 37-7, July 2002, p. A155), Jutta Zipfel et al. published an abstract re: Tafassasset. In the discussion part, the authors state: The figure illustrates that both samples have compositions clearly fractionated from CI and other chondrite groups. Tafassasset has AI/Mg and Mn/Mg ratios similar to other primitve achondrites, indicating incipient partial melting
Re: [meteorite-list] Ugliest Gibeon?
Hi Ken, This doesn't look like a Gibeon to me either. I believe the same individual also listed another large specimen that looked to me to be a Campo and listed it as a Gibeon. There is a lot of danger in guessing meteorites from looks but where there is money to be made, there are always those who will step over the line. It would be nice to have a little slice for etching purposes here. --AL magellon wrote: Greetings All: This has got to be the ugliest Gibeon I have ever seen: METEORITE 74lb. 33300gr. GIBEON. namibia RARE Item # 718994851 (If it is Gibeon, then it was adopted and raised by a family of Nantans ;) __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Tafassasset classification
Hi John and all, I believe that, in general, primative achondrites are no longer chondrites in that the rock has rxperienced melting and chondrules are no longer present. The rock has recrystallized and it has a crystalline texture. However, compositionally they remain the same as the parent chondrite material. So texturally they are achondrites, compositionally they are chondrites. If I remember correctly from my acapulcoite samples, a lot of metal is present between the crystals. In a regular differented achondrite, the metal has separated out as has other material and the resultant composition of the rock is significanrtly different from the parent body. As for the difference between a petrographic grade 7 and a primative achondrite, I agree that this line is fuzzy. Grade 7 chondrites should still have relict chondrules present. However, I believe that at least one acapulcoite (NWA725) also contains relict chondrules. This is my understanding of the subject. Hope it helps a bit but feel free to correct me if I'm not understanding this correctly. Regards, Frank - Original Message - From: John Divelbiss [EMAIL PROTECTED] To: fcressy [EMAIL PROTECTED]; Norbert Classen [EMAIL PROTECTED]; Bernd Pauli HD [EMAIL PROTECTED]; Svend Buhl [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Sent: Wednesday, October 02, 2002 8:19 PM Subject: Re: [meteorite-list] Tafassasset classification Frank, I understand the description of the primitive achondrite...including the types you mention. From that statement in Nortons book, they are still chondrites...just overdone a bit. What line did they cross to be called achondrites? And how does it relate to Tafassasset being also called a CR7? John - Original Message - From: fcressy [EMAIL PROTECTED] To: John Divelbiss [EMAIL PROTECTED]; Norbert Classen [EMAIL PROTECTED]; Bernd Pauli HD [EMAIL PROTECTED]; Svend Buhl [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Sent: Wednesday, October 02, 2002 10:55 PM Subject: Re: [meteorite-list] Tafassasset classification Hello John and all, Regarding your primative achondrite question, Norton's Encyclopedia of Meteorites has a page dedicated to the subject (P. 165). He states that primative achondrites have achondrite textures but still retain something of their chondritic composition. and that they are transitional between chondrites and achondrites. As examples of primative achondrites, he uses acapulcoites, lodranites and winonaites. Hope this helps. Frank - Original Message - From: John Divelbiss [EMAIL PROTECTED] To: Norbert Classen [EMAIL PROTECTED]; Bernd Pauli HD [EMAIL PROTECTED]; Svend Buhl [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Sent: Wednesday, October 02, 2002 5:05 PM Subject: Re: [meteorite-list] Tafassasset classification Hello All, Primitive is primitive!Help me to understand the differences please. Is the argument about where the line(s) should be drawn between a chondrite (that is really differentiated...like a 7) versus a primitive achondrite (that is not quite differentiated enough to be called a achondrite)? Is there really a 7 category and why? Are primitive achondrites now considered differentiated enough to be distinguished from a highly changed chondrite? small versus coarse grains in matrix? How is this line drawn? mineral makeup, level of glass, age, grain size/changes, etc. ? Lots of questions with this story. Alain would have something to say about all this. Ann Black, is there a position written from his corner? John __ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Tafassasset classification
In a message dated 10/2/2002 9:24:36 PM Mountain Daylight Time, [EMAIL PROTECTED] writes: I understand the description of the primitive achondrite...including the types you mention. From that statement in Nortons book, they are still chondrites...just overdone a bit. What line did they cross to be called achondrites? And how does it relate to Tafassasset being also called a CR7? Hello John, and Members, What an interesting way to put it: "chondrites, just overdone a bit". And maybe that is what Tafassasset is. Maybe it is just on the line (if there is one) or maybe it is the missing link between the achondrites and the chondrites. Here is the link to the report from Paris: http://www.impactika.com/Tafassasset.pdf Look at the diagram at the bottom of the first page. See how Tafassasset is plotted right between the CR chondrites and the Acapulcoites? I am sure the scientists on the List could explain that in much greater details. Anyway you look at it, I find it to be a very interesting meteorite, and very pretty too! Thanks for asking. Anne Black IMCA #2356 www.IMPACTIKA.com e-mail: [EMAIL PROTECTED]
