Dean-
Thanks for all of your patience in my recent e-mails concerning the abovementioed subject.
Below is the reply I received from Jeff, with my initial e-mail to him attached. Analyzing the olivines in a meteorite sample will not be an issue. So, if olivines are the main mineral phase of concern for H/L/LL classification, I can be of help to you also.
LIke I said earlier, 2 analyses would be $100
4 analyses would be $150
6 analyses would be $200
These analyses can be multiple analyses on one sample, or single analyses on several samples (i.e. 6 olivine and/or pyroxene analyses on one NWA or one olivine analyses on 6 seperate NWAs, or any combination thereof).
Hopefully, this has cleared the issue up for everybody involved. In summary, I can classify a sample as an H, L, or LL using the method discussed in Jeff's e-mail, I can get results to you faster than the institutions, and all sample material will be returned to you if so desired. Metamorphic grade, howver, will only be an estimate.
Any further thoughts? Hopefully, all of this info will persuade some of you to send some work my way. Please let me know what you think.
Sincerely,
Randy in N.O.
--- Begin Message --- For a proper classification of ordinary chondrites, one would normally make a quantitative analysis of the Fe/(Fe+Mg) ratio in olivine. This allows separation of H, L, and LL groups. We also do expect at least a rough estimation of metamorphic grade. One could also use pyroxene compositions, but the most comprehensive studies of ordinary chondrites focus on olivine, and so this is what everybody uses for classification. It's also a very simple mineral to analyze.
jeff
At 03:00 PM 7/6/2003 -0400, you wrote:
Dr. Grossman-
I am sure that you have recieved some e-mails concerning my classification of meteorites via electron microprobe. My approach is to differentiate between H and L chondrites, based on the presence of either bronzite or hypersthene pyroxene. Does this sound acceptable? Most schemes I've seen use this nomenclature. Of course, this does not cover the problem of metamorphic grade, but I want to classify between Hs or Ls based on this information.
It sounds like there is a lot of potential to do so, and it would help me immensely if I could get this approved for the ordinary chondrites. As far as my background, I have a BS and MS in Geology (geochemistry and petrology) and a vast amount of experience with the equipment.
Any thoughts?
Randy in N.O.Dr. Jeffrey N. Grossman
Chair, Meteorite Nomenclature Committee (Meteoritical Society)
US Geological Survey
954 National Center
Reston, VA 20192, USA
Phone: (703) 648-6184 fax: (703) 648-6383
--- End Message ---
