GSA Bulletin: Common lead,Sm Nd,and U Pb constraints on.
U/Pb zircon ages as old as 3.2 Ga have been found in the Marshfield terrane.(Van Schmus and Anderson,Grinding and powdering was done in ceramic mills.Following crustal thickening,heating,and melt ing during the Penokean.
US Industrial Garnet USGS Publications Warehouse
Apr 17,2003Georgia,ShowiNg the locatioNS of couNtieS aNd iSogradS of TacoNic garnet,140,000 t of ilmenite,12,000 t of zircon concentrate.Contact Us