A 1600 square km portion of Dominion Mining's Gawler Project acreage, centred on ELs 3044 and 3270, has been explored for possible economic nickel sulphide mineralisation under a joint venture with Mithril Resources, which was in force during the period 12/12/2005 to 30/6/2009. Under this agreement Mithril undertook to spend up to $5 million over six years to earn 75% of the rights to any ensuing nickel discoveries. The preferred targets, envisaged as likely to exist within faulted Proterozoic basement rocks of the Fowler Domain, were Thompson Nickel Belt style massive sulphide mineralisation associated with deformed pods of ultramafic rock which have been remobilised into structural traps, or Voisey's Bay type nickel mineralisation occurring in volcanic feeder pipes that may have formed between magma chambers and the contemporary palaeosurface. The Fowler Domain is a broad curvilinear belt of anatomising shear zones, which may have facilitated the intrusion and extrusion of mafic-ultramafic rocks. Mafic and ultramafic rocks are known to occur throughout this part of the western Gawler Craton as mafic dykes and lamprophyres, which are possibly co-genetic and related to the Neoproterozoic Gairdner Dyke Swarm event. In addition, numerous mafic and ultramafic subcrop lithologies have been recorded on previous drillhole stratigraphic logs, e.g. gabbro, peridotite, lherzolite, norite, and pyroxenite. The most significant of these come from the Aristarchus ultramafic intrusion that was first drilled by PIRSA, which contains minor nickel-copper sulphides. The age and relationships between these mafic-ultramafic rocks are unknown, although costeaning, mapping and drilling done by previous explorers and PIRSA over the Aristarchus and nearby Blackfellow Hill such occurrences do suggest that they were intruded as dykes at some time after the upper amphibolite-granulite facies metamorphism episode that affected their host rocks. As evidence, the PIRSA Aristarchus drill core displays intrusive contacts with the host gneiss/foliated granite, and the undeformed nature of the ultramafic suggests it was intruded post-metamorphism. Furthermore, a trench excavated in the Aristarchus area by Pacific Exploration Consultants in the early 1980s showed that a westwards-dipping ultramafic dyke at least 50 m thick was intruded into felsic schist. To begin its investigations, Mithril examined Dominion's existing database of calcrete sampling geochemical results, and this, combined with a review of PIRSA's regional RAB/RC drilling results, identified fourteen localities needing further work. Additionally an interpretation of the available aeromagnetic data revealed twenty-nine magnetic features that it was thought might represent signatures of buried mafic/ultramafic potential host intrusive bodies. During March 2006 Mithril conducted orientation geochemical sampling of the regolith within three of the joint venture licence areas, collecting 73 soil and 11 rock chip samples for analysis. The highest nickel value returned from the soil samples was 0.55% Ni, while the maximum soil copper value was 241 ppm Cu. In comparison, the highest nickel found in the rocks was 0.25% Ni, and the peak copper content was 151 ppm Cu. A field reconnaissance of the calcrete and magnetic anomalies led to a preliminary programme of aircore drilling (62 holes for a total penetration of 1897 m) being performed during May-June 2006. A fine-grained mafic rock was penetrated in one hole (DMAC013), however, the majority of the other bottomhole lithologies were gneisses and iron-rich gneisses, grading up to banded iron formations. Thick profiles of basement sapropelic clays were encountered in most of the holes, providing a sampling medium that may have concentrated elements from nearby mafic hosts or weathered sulphide mineralisation. The northernmost hole intersected a 60 m thickness of sedimentary clay and fine-grained sand probably belonging to the Eromanga Basin. Several of these aircore drillholes displayed significant and, in some cases, coincident nickel, copper and chromium anomalism. The highest Ni value obtained was 3642 ppm, the highest Cu was 325 ppm, and highest Cr was 3415 ppm. The anomalous assay results came from horizons near the top of the regolith profile, wherein selected 1 metre and 3 metre intervals had been sampled. The regolith geochemistry suggested to Mithril that mafic/ultramafic lithologies and/or Ni-Cu sulphide mineralisation are in active process of weathering near these drillholes, and accordingly it was decided that such localities clearly warranted follow-up drilling or ground EM surveying. In the subject portion of the Fowler Domain, a substantial additional coverage of RAB drilling had already been generated by Dominion as part of its gold exploration activities during the 1990s. However, the drill cuttings from these holes had only been analysed for Au, As and occasionally Cu: unfortunately, the pulps were no longer available. However, heaped RAB drill cuttings still remained at the drill sites, and the metre splits were still visible for most of the holes. Consequently, Mithril decided to conduct a hole re-sampling programme in areas that had been drilled by Dominion and were now deemed prospective for nickel, by revisiting the old drill sites and taking 1-2 m sample intervals of lithologies in selected horizons and at the bottom of each hole. 288 samples were taken from 144 RAB drill sites that had been put in on approximately 200-300 m centres. In common with Mithril's aircore drilling disclosure, several of the resampled Dominion RAB drillholes displayed significant regolith nickel, copper and chromium anomalism. The highest Ni value was 1972 ppm, the highest Cu was 746 ppm, and the highest Cr was 1924 ppm. Again, selected one and two metre intervals at the top of weathered horizons in the old drillholes were those showing high assay values. A moving loop ground EM survey was conducted for Mithril by Solo Geophysics during October 2006 over six of the anomalous regolith targets. A total of 30.2 line km of EM profiles were acquired along 22 lines. This geophysical work was successful in identifying related subsurface conductive targets of varying quality. Areas 1 and 14 were found to contain the most significant EM responses, although targets at areas 3, 10 and 15 all appeared to have good magnetic correlation. During March 2007 a follow-up ground EM survey was performed down to 200 m line spacing to further resolve the conductive features previously identified at Areas 1 (Aristarchus), 3, 10 and 14. A total of 262 moving loop EM soundings were collected along 8 lines covering 13 line km at Aristarchus and Area 14. A further 150 fixed loop EM soundings covering 3.75 line km were also collected from 2 transmitting loops over Areas 3 and 10. This work was successful in resolving five conductive late time EM anomalies representing potential massive sulphide targets at Aristarchus and Area 14, but downgraded the targets at Areas 3 and 10. In late April 2007 Mithril commenced diamond drilling to address the four high priority EM anomalies identified in Area 1 (Aristarchus prospect). Only three drillholes were eventually completed for a total penetration of 873 m, of which 287 m was RC percussion precollars and 586 m was NQ diamond coring, due to slow drilling progress caused by broken ground conditions. Hole DMDD001 targeted the central of the three most prominent ground EM anomalies there. The hole was drilled at 60 degrees declination to the west to intersect a modelled conductive body at ~220 m downhole depth. The RC percussion precollar was drilled to a depth of 96 m, beyond which coring proceeded with NQ rods to a total depth of 234 m. The hole was cased with 50mm PVC to allow for later downhole EM surveying. Two core samples of deformed mafic to felsic gneissic rock containing fine-grained disseminated sulphides, from 121.65 m and 145.1 m depth, were submitted to Ian Pontifex for polished thin section examination. The descriptions recorded that the mafic portion of the gneiss was likely to be a deformed gabbroic intrusive. The sulphides were confirmed to be predominantly pyrite and chalcopyrite. This first exploratory hole had been terminated when it became apparent from inspecting cored rock fabrics that the hole from ~165 m depth was following the bedrock strata down dip, and because no conductor had been intersected at the modelled depth. Remodelling of the EM data was then carried out, confirming that a modelled conductor positioned ~200 m to the east, with a westerly dip, could explain the observed surface EM profiles. The drilling rig was therefore moved to a new site ~90 m eastwards, where a new angled hole DMDD002 was collared, directed downwards at 70 degrees towards the east to try to meet the target conductor at 260 m downhole depth. However, during the drilling the hole trajectory steepened, thereby increasing the target depth. Similar rocktypes were encountered in this drillhole as in DMDD001. The disseminated sulphides (to ~8%) intersected as thin blebs and stringers within the pyroxenite-gabbro unit cored from the depth interval 307.44-307.89 m are interpreted to be the targeted conductor horizon. Polished thin section examination of a portion of the pyroxenite has confirmed the presence of disseminated, interstitial magmatic sulphides which include pentlandite and violerite. Analytical results also returned anomalous values of 0.16% Ni and 230 ppb Pt + Pd, supporting the magmatic origin of the sulphides. A third PACE-subsidised diamond hole, DMDD003, was drilled to the east of DMDD001, to TD 321 m, targeting the easternmost ground EM anomaly detected at Aristarchus. This hole failed to encounter any basement conductor. All three diamond drillholes completed at Aristarchus prospect were cased with 50 mm PVC pipe, so that downhole EM logging could be done later. When the logging work was carried out during September 2007, no off-hole conductors could be identified. This result indicated that the previous data models based on the surface EM were incorrect; subsequent remodelling of the surface responses suggested that they arise from edge effects of a shallow, moderately conductive plate-like feature (e.g. saline overburden sediments). During June 2007 grid-based geochemical sampling of magnetic lag was undertaken by Mithril on a 1 km x 500 m spacing over a large, mostly sand-covered aeromagnetic anomaly lying to the west and south of Aristarchus, which was interpreted to reflect a gently north-eastwards dipping mafic intrusion. 102 lag samples were collected and assayed. Anomalous Ni/Cu/Pt was found on the southern edge of the interpreted magnetic source body. Broadly spaced ground EM traverses were made over this location, and they identified coherent mid-time conductive anomalies similar in character to those that had been drilled at Aristarchus. Consequently, it was recommended that additional, RC drilling be undertaken to determine if the respective anomalies represent buried sulphide mineralisation. The magnetic lag sampling also revealed some elevated gold values (to 103 ppb Au) in the western part of the grid, which Mithril suggested should warrant follow-up by its joint venture partners Dominion Mining and Southern Gold. No other nickel exploration field work was done on the subject licence areas during the period October 2007 to July 2009 (when Mithril's joint venture with Dominion Mining ceased).