The occurrence of intermediate schorl-dravite and alkali-deficient, Cr-(V)bearing tourmalines in the volcanic-sedimentary sequence of the Serra do Itaberaba Group - SP - Garda, Gianna Maria; Beljavskis, Paulo; Juliani, Caetano; Silva, Dailto; Rocha-Campos, A. C. (Anais da Academia Brasileira de Ciências, 2002)