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We document various textural occurrences of greenockite associated with several ore minerals in varying parageneses: pyrite + sphalerite + galena + chalcopyrite ± arsenopyrite ± pyrrhotite ± bornite ± tennantite ± tetrahedrite ± covellite ± chalcocite ± aikinite ± wittichenite ± matildite ± berryite ± miharaite ± geocronite ± hematite ± magnetite from mineralized samples of the Caledonia Group mines, Marayes mining district, La Huerta Range, San Juan province, Argentina, based on reflected light and scanning electron microscope investigations. The mineralization is hosted mainly in metacarbonate outcrops in contact with the granulite basement and associated intermediate to mafic meta-intrusive rocks. We recognize three types of greenockite on the basis of textural and chemical criteria. Type-1 greenockite contains less than 1 mol.% ZnS, but its Fe content varies from 0.2 up to 4.5 mol.% FeS. Type 2 is Zn-rich, with 10-25 mol.% ZnS component and <0.1 to 3 mol.% FeS component, and type 3 has a Zn content of 5-7 mol.% ZnS component and FeS <0.1 mol.%. The presence of complex Ag-Cu-Bi-Pb sulfides point to a latestage, low-temperature overprint of the primary sulfide parageneses, accompanied by the formation of hypogene greenockite, at least partly at the expense of sphalerite. The near-end-member composition of greenockite and late-stage sphalerite also indicates a low temperature of formation.

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Within the Ötztal complex (Öc), migmatites are the only geological evidence of the pre-Variscan metamorphic evolution, which led to the occurrence of partial anatexis in different areas of the complex. We investigated migmatites from three localities in the Öc, the Winnebach migmatite in the central part and the Verpeil-and Nauderer Gaisloch migmatite in the western part. We determined metamorphic stages using textural relations and electron microprobe analyses. Furthermore, chemical microprobe ages of monazites were obtained in order to associate the inferred stages of mineral growth to metamorphic events. All three migmatites show evidence for a polymetamorphic evolution (pre-Variscan, Variscan) and only the Winnebach migmatite shows evidence for a P-accentuated Eo-Alpine metamorphic overprint in the central Öc. the P-t data range from 670-750 °c and < 2.8 kbar for the pre-Variscan event, 550-650 °c and 4-7 kbar for the Variscan event and 430-490 °c and ca. 8.5 kbar for the P-accentuated Eo-Alpine metamorphic overprint. U-th-Pb electron microprobe dating of monazites from the leucosomes from all three migmatites provides an average age of 441 ± 18 Ma, thus indicating a pervasive Ordovician-silurian metamorphic event in the Öc.

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