Adularia-sericite type wallrock alteration at the María Josefa gold mine: An example of low sulfidation epithermal ore deposit, within te volcanic Rodalquilar Caldera (SE, Spain)
AbstractThe mineralogy of wallrock alteration in Maria Josefa mine was investigated in order to establish the paragenetic mineral association and their origin in the framework of the gold-alunite Rodalquilar mining district (SE Spain).Microprobe analyses exhibit two types of adularia existing in the aureoles of the Maria Josefa vein system reflecting the evidence of both replacement and neoformation dunng the alteration process. Three paragenetic association have been recognized: quartz-adularia, quartz-adulana-sencite and quartz-sericite. X-ray diffraction analyses were performed in order to identify and quantify the existing minerals. The data obtained indicate the presence of minor amounts of kaolinite, goethite, hematites, calcite, gypsum and jarosite. Pynte was identified as the principal base metal-containing mineral. The mineral paragenetic assemblages found in wallrock alteration at the Maria Josefa mine present a good example of low sulfidation type of epithermai gold deposit located penpherally to the Rodalquilar caldera structure, contrasting with the high-sulfidation type existing in the core.