tourmaline in granitic pegmatites and their gountry rocks ... - RRuff

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In the northwestem part of the province of Salamanca (Spain), many Li-, .... northwestern Salamanca, is bordered by the Lumbrales ...... Ac ta 2, 229 -242.
835 The CanadianM irc ralogist Vol. 33,pp. 835-848(1995)

TOURMALINE IN GRANITICPEGMATITES ROCKS, AND THEIRGOUNTRY FREGENEDA AREA,SALAMANCA.SPAIN ENCARNACI6N ROpa, ALFONSO PESQIIERA ANDFRANCISCOVELASCO y Petrolagfa,Universidad Departamento d.eMineralagta Aptdo,644,848080,Bilbao,Spain delPatsVascolEHU, ABSTRACT In the northwestempart of the province of Salamanca(Spain),many Li-, Sn-bearingand barrengranitic pegmatitesoccur. Thesebodiesdisplay a zonal distribution northwardfrom the Lumbralesgranite,with a degreeof evolution increasingwith distancefrom the granite contact.Tourmaline appearsas an accessorymineral in the barren pegmatites,as well as in their country rock In both cases,the tourmalinebelongsto the schorl-dravitesolid-solutionseries.Tourmalineshowstexfiral and conpositional variations in relation with pegmatitetype. Subhedralto euhedralprismatic, very fine- to medium-grained (