ON CONNECTION OF NOBLE-METALS SORPTION CA PACITY OF CARBONACEOUS MATTER OF ROCKS WITH THE MATTER STRUCTURE

Data on platinum contents in samples from various carbonaceous rocks o f North-West and North-East Russian, Kazakhstanian, and Uzbekistanian gold deposits have been obtained. A wide range of platinum contents ha s been found (1 to 4 orders of magnitude), increased level of backgrou nd contents (3 . 10(-6) to 6 . 10(-6)%) as well as possibility of accu mulation enormous quantities of Pt within some localities of the depos its. To estimate platinum group elements (PGE) concentrating mechanism by carbonaceous matter of rocks the connection of Pt(IV) and Pd(II) s orption capacity with structure of the matter has been studied. It is shown that increasing degree of organic matter (OM) alteration in rock s during diagenesis and metamorphism leads to decreasing oxygen-contai ning functional groups' contribution in the OM structure and correspon ding decreasing its PGE sorption capacity by more than one order of ma gnitude. Complex formation mechanism of sorption process is the main r eason of PGE concentration in the carbonaceous rocks.