re-evaluated [e.g. Oka (Canada); Fen (Norway); Panda Hill (Tanzania)] for their economic potential. Although...only operating Nb mine in under-saturated peralkaline syenites is the Karnasurt mine (Kremenetsky et al...melilitite–nephelinite complex of Kisingiri-Rangwa, Kenya (Le Bas, 1977). Here an eroded volcanic cone consisting...units presents in carbonatites e.g. the Loolekop mine at Phalaborwa (Fig. 250 of Woolley, 2001), Catalão-I...cross-section of the Kisingiri-Rangwa volcanic centre, Kenya. After Le Bas (1977). Please cite this article