Quantitative proton microprobe trace element analyses of sulfides from Sudbury and Still- water

Abstract

Major sulfideore mineralsfrom mineraldepositsin the Sudbury area, Ontario, and from the Stillwater Complex, Montana, havebeenanalyzedwith the Heidelbergproton microprobein asearchfor tracequantitiesof theplatinum- group elements@cE). No PGE were detectedin Sudbury sulfides,down to minimum detection-levelsof 1.2to 3 ppm for Pd and Rh and 50-60 ppm for Pt. Stillwater pentland- ite, on the other hand, containstlre following pGE in solid solution:Pd 1870to 13600ppm, Rh < 26to ll0 ppm, and Ru < 14 to 80 ppm. Chalcopyrite,pentlanditeand pyr- rholite from Sudbury and Stillwater contain Sein solid so- lution. Sudburychalcopyrite,in addition, containsZn in the form of a heterogeneousolid-solution( < 35 to 2520 ppm).Thedatademonstratethegxeatpotentialofthe pro- tonmicroprobeinresearchonthegeochemistryofsulfides and other minerals. The low levels determined for extenr of solidsolutionof thePGEin Sudburysulfidesarehelp- ful in guiding future mineralogical researchand in direct- ingimprovementsinPGErecoveriesT.hedataonStjllwater sulfides help understand distribution of the PGE in other Merensky-typedepositsand will also assistmetallurgists in improving metalrecoveries,shouldtle Stillwaterdeposit be exploited. Data on other trace-elementsare of interest in questionsconcerningore genesisand flotation research.