IANIGLA   20881
INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
artículos
Título:
Huréalita Mn2+5(H2O)4[PO3(OH)2(PO4)2 de diferentes yacimientos del distrito pegmatítico totoral, San Luis, Argentina
Autor/es:
OYARZÁBAL, JULIO CÉSAR; GALLISKI, MIGUEL ANGEL
Revista:
Revista de la Asociación Geológica Argentina
Editorial:
Talleres del Instituto Salesiano de Artes Gráficas
Referencias:
Lugar: Buenos Aires; Año: 2007 vol. 62 p. 210 - 210
ISSN:
0004-4822
Resumen:
Hureaulite, a hydrated manganese (II) phosphate mineral, has been found in three different pegmatites of the Totoral pegmatitic field, San Luis ranges, Argentina. In Santa Ana mine, a berillium-bearing pegmatite located in the Cerro La Torre group, this phosphate mineral occurs with eosphorite as little prismatic idiomorphic crystals hosted over sicklerite exfoliation surfaces, and derivates from the hydrothermal alteration of primary lithiophilite. In Ranquel berillium-bearing pegmatite, located in the Loma Alta group, hureaulite is associated with ferrisicklerite, purpurite, phosphosiderite, strengite, reddingite, meta-autunite, eosphorite, vivianite and hydroxil-apatite and has been formed by extreme weathering of triphylite; the crystals are 5 mm in length and show typical monoclinic forms. In San Luis II, a lithium-bearing pegmatite located in the Paso del Rey group, hureaulita has been found as shot prismatic crystals or fine scabs intergrowed between fibrous dufrenite, in association with ferrisicklerite, bermanite and carbonate-fluorapatite and formed by extreme hydrothermal alteration of primary lithiophilite. Hureaulite in different occurrences shows similar physical and optical properties, but  differs in chemical Fe-Mg-Ca octahedrical substitutions, according whit the secondary phosphate mineral that conforms assemblages.      Key words: huereaulite - phosphate mineral - pegmatites - Totoral pegmatitic field