Composición y propiedades de minerales de niobio y tantalio de las pegmatitas graníticas de El Quemado, Provincia de Salta

GALLISKI M. A. LOMNICZI DE UPTON I.

Revista de la Asociación Geológica Argentina

Instituto Salesiano de Artes Gráficas

Lugar: Buenos Aires; Año: 1992 vol. 47 p. 323 - 331

0004-4822

ABSTRACT. Composition and physical properties of Nb and Ta minarais from granitic pegmatites of El Quemado, SaltaProvine. The ocurrence, X-ray crystallography, physical properties and chemical composition of four Ta-Nb minarais fromgranitic pegmatites in the El Quemado area are described. Disordered ferrocolumbite occurs in beryl-type pegmatites as blackcrystals of (Feo49 Mno„)(Nb„„ Tao os Woo„), 06. Magnatotantalite in brown centimetre-sized crystals (Feose Mno„)(Nbo,Taosi Tio02)andmicrolite(Cato illvo„Uvio.,Nao„Ko „ Fe„Qo (Tam, Nbood Alo.14 )2 06 (0,22 °Ho isFo ill smali"talladral crystals,are present in complex, spodumene subtype pegmatites. Ixiolite wasfound as centimetre-sized nodules of(I gbo Tat„ Ti„„ Feo ,Mno„), O, composition. Ta/Nb and Mn/Fe fractionationtrends within the pegmatitie indicated by chemical analysis ofTa-Nb pitases, show a lithium-rich pegmatitic process enhanced by high F activity.