Anomalous concentrations of PGE in the Cu-ores at the Tisová deposit
Abstract
Anomalous concentrations of Pt (33-4740 ppb, average 1225 ppb) accompanied by low Pd values (2.6-3.7 ppb), have been detected in seven ore samples from the Tisová Cu deposit, considered to be of the Besshi-type deposit. Pd/lr and Pd/Pt ratios are close to those in tholeiitic basalts. Mantle normalized Ni-lr-Ru-Rh-Pt-Pd-Cu patterns in ore samples from Tisová show significant Pt and Rh enrichment when compared to Besshi deposit (Japan) and other volcanogenic massive sulfide ore deposits of the Iberian Pyrite Belt (e.g. Neves Corvo and Rio Tinto). The studied ore samples are characterized by the presence of pyrite, pyrrhotite,) chalcopyrite, arsenopyrite, sphalerite, native Bi, jamesonite, cobaltite, willyamite, and Fe-oxide (limonite). Mineralogical and subsequent LA-ICP-MS study has not resulted in the identification of principal PGE phases. Likely, Pt occurs as Pt-Fe oxide but the presence of other PGE discrete PGM on the boundary of sulfide grains and/orclose relationship can not be excluded.