Résumé
Analyses are presented of Os, Ir, Ru, Rh, Pt, Pd and Au in sulphides in olivine macrocrysts from the Udachnaya pipe, Siberia, Russia, fertile garnet peridotite, Kaapvaal, South Africa, mantle peridotite xenoliths in alkali basalts from E Australia (Mts Gambier, Quincan; Allyn River) and lherzolite from the Pyrenees. The results confirm that HSE are strongly concentrated in mantle sulphides and not in coexisting silicates. Two textural and compositional types of sulphides occur in mantle-derived peridotites: in depleted S-poor samples, and interstitial sulphides rich in Ni or Cu. The results show that these sulphides do not have chondritic HSE patterns; different generations of sulphides contain variable HSEs in relative abundance. Non-chondritic HSE patterns reflect processes in the upper mantle-melting and sulphide addition via metasomatism.