As part of the PACE Year 2 collaboration between PIRSA and the minerals industry, PepinNini Minerals proposed and was granted part subsidy funding for an extensive drilling programme in the western APY Aboriginal Lands of South Australia, to examine previously untested layered mafic intrusions of the Giles Complex. The target was potential massive nickel-copper sulphide mineralisation similar to that found at the Voisey's Bay deposit in Newfoundland, Canada, as well as any platinum group precious metal mineralisation of Platreef, South Africa, style. During April-May 2006 PepinNini used a track-mounted SD400 percussion drill rig to investigate a variety of targets associated with two prominent ultramafic/mafic intrusions within its EL 3368, namely, the [Mount] Harcus Intrusion, which is a remanently magnetised sub-vertical body approximately 300 m wide and extending over 6 km along strike, and, lying 45 km away to the north-west near Mount Moulden, the Purananja Intrusion, a body with similar inferred dimensions. The targets were generatedfrom interpretations of airborne magnetic data produced under the TEISA initiative of PIRSA, and from airborne electromagnetic survey data, from ground based electromagnetic surveys, surface geochemical sampling, and geological mapping. 21 RC drillholes, plus one water bore, were completed for a total of 3111 m. 14 holes ranging in depth from 43 to 211 m were drilled on and around the Harcus Intrusion, while 7 holes ranging in depth from 91 to 222 m were drilled at the Purananja Intrusion. Drilling intersected massive, sub net-texture and disseminated forms of sulphide mineralisation that are associated with the Harcus Intrusion. Hole RC06HAR009 drilled under thin cover on the eastern side of the intrusion discovered the sulphides within a pyroxenite that was encountered over the entire drilled depth interval 1-91 m, including a zone from 48-50 m depth which carried the massive mineralisation having maximum metal values of 0.45% Cu and 0.13% Ni. Minor to blebby disseminated sulphides were also encountered in later drilled holes RC06HAR012 and RC06HAR013 that were drilled respectively 40 m north and south of the discovery hole. Subsequently, weak disseminated copper sulphide was also seen at the Purananja Intrusion in thin pyroxenite layers cut by drillholes RC06MTM005 and RC06MTM007. The sulphide assemblage encountered is dominated by pyrrhotite but is also accompanied by modest proportions of chalcopyrite and possible pentlandite. The presence of a mixed sulphide mineral assemblage confirms sulphur saturation in the intruded magma, and therefore the potential for finding primary sulphide ore accumulations within the targeted mafic intrusions. The successful identification of sulphide mineralisation at this early stage of drilling provides a focus for further intensive exploration activities in the expectation that other proximal targets will represent hidden intrusions that may also contain sulphide mineralisation.