To all who are interested in this: In geology we use the term "weathered" or "altered" for rocks where the *majority* of minerals have been replaced by a weathering product (Fe-oxides, usually, in the case of chondritic meteorites). If the rock is a real basket case we put the word "severely" in front of "weathered". It seems to me that "relict" is sugar-coating the fact that such meteorites are really severely weathered (W6) and have very little (<5%) of the original mineralogy visible.
Perhaps the NomCom should add a W7 to Wlotzka's 1993 weathering grade scheme to take care of the terminology issue. Matt Morgan David Weir wrote: > >Since the new category of relict (or fossil) meteorites was adopted by >the Nomenclature Committee only this past October, I would imagine there >are likely other relict meteorites in our collections which have not >been so designated. The definition requires that more than 95% of a >meteorite has been replaced by secondary phases since its fall. The >meteorite Mills comes to mind as a possibility, but maybe its not quite >there yet. > >David >______________________________________________ > >\ > > ______________________________________________ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list