“…Cr and Mn have a high affinity with Fe-oxides (Yu et al 2001), such as hematite and magnetite, and with the minerals of the primary mineral assemblage such as Fe-augite and Fe-hornblende. V, Cu, Zn, and W mainly occur as relevant trace elements in the minerals of the primary and accessory mineral assemblages such as apatite, biotite, F-titanite, Fe-augite, Fe-hornblende, Fe-Ti oxides and ilmenite (Landergren 1978, Wedepohl 1978a, 1978d, Krauskopf 1978. Concentrations of Nb (between 53.00-64.00 ppm), LREE (between 7.50-73.00 ppm) and Ta (between 2.30-6.40 ppm) could be related to Nb, LREE and Ta concentrations in the rhyolites from the Thomas Range.…”