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S 13C/12C and 18O/16O ratios have been measured for 42 marbles from the main quarry localities of archaeological interest of Western Anatolia (Marmara, Ephesos, Aphrodisias, Denizli and Afyon) in order to test the possibility of isotopically characterizing ancient marbles from this region. The various groups of samples are not clearly distinguishable on a δ13C‐δ18O diagram. However, if only white or slightly coloured samples are considered, the isotopic method appears to be much more selective.

A large number of samples containing sulfides, sulfosalts and cassiterite from the Corvo volcanogenic massive sulfide deposit, exploited at the Neves-Corvo mine, southern Portugal, were analyzed using electron and proton microprobes after a detailed examination by reflected-light ore microscopy. The samples are representative of the main four types of ore: cupriferous rubané ore, rubané ore with tin, cupriferous massive sulfide ore and cupriferous massive sulfide ore with tin. The trace-element distribution among the minerals from the four ores, and particularly the high Sn and In contents as well as the Se/S values of pyrite, provide evidence of a magmatic signature for this complex and unique deposit. With respect to cassiterite, which is a characteristic major ore mineral at the Corvo deposit, both chemical composition and textural relationships to sulfides suggest that the high-temperature reduced fluids that deposited sulfides also deposited cassiterite. The mineralogical and geochemical data support the field hypothesis of an allochthonous origin for rubané ores, inferred to be a part of the stockwork of massive mineralization, thrust on the top of massive ores during the Late Hercynian.

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