Hello all, Thank everybody for information about the Ti/rutile in garnet problem. I also received some e-mails on the topic beside the discussion-list. The most interesting one is about measurements on natural garnets and experiments done by A. Brandelik (Stuttgart/Germany) who is currently working on a Ti-in-Grt Thermometer/Barometer. There was an abstract in an 1998 AGU volume. cheers horst Massone HJ & Brandelik A (1998) Ti in Al-Garnet - a Newly Calibrated Geothermobarometer for HP and UHP Metamorphic Rocks. EOS, Transactions, AGU Fall Meeting, Vol 79, No.45 November 10, 1998/Supplement (page F972) ================================= Horst Marschall Mineralogisches Institut Universitaet Heidelberg INF 236 69120 Heidelberg ++49-(0)6221-546021 [log in to unmask] =================================