Hello Kostas, You could try looking at: Bea, F., 1996. Residence of REE, Y, Th, and U in granites and crustal protoliths: Implications for the chemistry of crustal melts. Journal of Petrology, 37, 521-552. Take care, Greg ----- Gregory Dumond Assistant Professor, Structural Geology and Tectonics Department of Geosciences University of Arkansas Fayetteville, AR 72701, USA ________________________________________ From: Metamorphic Studies Group [[log in to unmask]] on behalf of Kostas papapavlou [[log in to unmask]] Sent: Friday, March 06, 2015 11:09 AM To: [log in to unmask] Subject: [geo-metamorphism] REE in accessory phases Hello, I'm trying to find in the literature studies of titanites and apatites that show HREE enrichment patterns, if anyone could suggest any studies i would appreciate it. Kind regards, Kostas