PLATINUM-GROUP MINERALS IN FLUID INCLUSIONS FROM THE MARATHON DEPOSIT, COLDWELL COMPLEX, CANADA

Platinum-group minerals (PGM) project into fluid inclusions that occur in chalcopyrite and cubanite from the Marathon deposit, Two Duck Lake gabbro, Coldwell Complex, Ontario. Semi-quantitative analyses of the micron-sized PGM were made by SEM-EDS; they reveal Ag-bearing intermet allic compounds of Pd3Sn-Pd3Pb-Pd3Te (i.e., atokite-zvyagintsevite-kei thconnite) and telargpalite (Pd2AgTe) on broken, irregular surfaces of the Cu-Fe-S minerals. Halite daughter minerals, and quenched brine oc cur in and around some opened fluid inclusions. These data confirm the hypothesis based on petrography and mineral compositions that saline fluids remobilized PGE, Cu, and other elements and precipitated them w ell after crystallization of sulfide and silicate magmas in the Marath on deposit.