NWA 773 is not a Norite. NWA 773 The cumulate is coarse grained and the thin sections are small, so the modal mineral proportions obtained from different sections do not agree well. Because augite and pigeonite, both clinopyroxenes, dominate over orthopyroxene, which is at most "minor" (Korotev et al., 2002), the cumulate is a gabbro, not a norite. Specifically, it is an olivine gabbro because olivine exceeds 10%. If plagioclase is actually <10%, then it's a peridotite
Here is a link that will clarify the misclassification: http://epsc.wustl.edu/admin/resources/meteorites/nwa773.html Kind Regards, Adam ______________________________________________ Meteorite-list mailing list [email protected] http://six.pairlist.net/mailman/listinfo/meteorite-list
