Pegmatitos graníticos de Namirroé - Nuaparra, Zambézia, Moçambique : Estrutura e mineralogia

ABSTRACT: At the core of the Granitic Pegmatite Province of Zambezia in Mozambique, in the Alto Ligonha Pegmatite District, a group of distinct types of pegmatites outcrop and are trapped by the same set of strike slip and overthrust structures. The most frequent are beryllium-rich with some Bi and Nb-Ta oxides (with anomalous contents of W). Their primordial, zoned, inner structure is well developed — giant crystals of K-feldspar at the intermediate zone are conspicuous, as is rose quartz in huge quantities at the cores. At close proximity, LCT typical pegmatites do occur. On the basis of mineralogy, structure, and cartography, and considering the paragenetic contrasts and the emplacement in the same set of large-scale structures of tectonic transport, it is reasonable to accept that this area corresponds to a material frontier between distinct districts or pegmatite fields.