Pyroxene europium valence oxybarometer: Effects of pyroxene composition, melt composition, and crystallization kinetics Shearer, C. K. ; Papike, J. J. ; Karner, J. M. Abstract Publication: American Mineralogist Pub Date: October 2006 DOI: 10.2138/am.2006.2098 Bibcode: 2006AmMin..91.1565S