Exploration for possible economic gold occurrences in an area surrounding Outalpa Hill in the Olary Ranges, 25 km north of Manna Hill township, has been conducted initially by a private prospecting syndicate with the assistance of industry professional geological consultants, and later by Placer Exploration Ltd under a joint venture agreement signed in mid-1990. Early attention was focussed on the historic Walparuta copper and gold mine, located 7 km north of Weekeroo Homestead, where recorded sporadic production made between 1894 and 1953 totalled 23.5 tons of ore yielding 8 oz 18dwt of gold. Amona Mining performed gold ore processing trials on grab samples taken from shaft walls and dumps at the old workings, and also commissioned some petrographic studies. Preliminary rock chip sampling and soil sampling carried out on a 50 m x 25 m grid revealed a gold-copper geochemically anomalous zone 1 km in length surrounding the mine, entirely within a biotite-magnetite rich quartz-feldspar gneiss, with a possible further extension towards the south-west as indicated by a strong magnetic ridge and outcrops of similar gneiss. In view of the apparent extent of ground requiring evaluation, the licensee syndicate decided to farm out a half-share to interested third parties having the technical calibre and financial capacity to mount a thorough exploration programme. BHP Minerals and Placer Exploration both indicated an interest in the Walparuta project, and after conducting field visits in early 1990 Placer geologists signed a joint venture agreement for work including an early drilling appraisal of the prospect's potential. After assuming the licence operatorship, Placer Exploration conducted geological mapping, further rock chip and soil sampling, the reprocessing and interpretation of available aeromagnetic data, BLEG stream sediment sampling, and grid-based ground magnetic, Sirotem and gradient IP surveys over the eastern half of the Weekeroo Inlier. The geochemical work showed that the eastern margin of the inlier had the most prospectivity, with encouraging copper, gold, barium and silver anomalism present in both stream and rock chip samples. A ground magnetic survey carried out at Walparuta prospect revealed the presence of a north-south trending sequence of highly magnetic rocks, resolvable into three magnetic units that were interpreted as representing a single tightly folded magnetite-bearing horizon. Conversely, detailed 50 m spaced ground magnetic data acquired at the Walter Outalpa prospect during early 1991 indicated that the gold-only mineralised rocks there appeared to correspond to a ~ 100 m wide zone of low magnetic susceptibility, also aligned north-south. However, the likely strong structural control of the Walter Outalpa deposit by a shear zone was thought to limit the scope for finding additional gold mineralisation there, as no related shear splays were delineated by the magnetic data. A gradient array IP survey was also conducted at Walter Outalpa to try to detect if there is concealed gold mineralisation within the known limits of the shear zone. Only a weak ENE trending IP chargeability response was obtained, that was attributed to the continuation at depth of outcropping pyrite-chert and quartz veins. With its exploration attention therefore concentrated on the Walparuta prospect, Placer conducted 1:1000 scale mapping and constructed a 570 m long measured section traversing the entire mineralised rock sequence exposed along the bed of Dead Sheep Creek. Channel samples and magnetic susceptibility measurements were taken at 2, 5 and 20 m intervals across this section. A comparison was then made between the rock geochemistry of unmineralised country rock banded iron formation units, which had been subdivided by Placer geologists into four levels mappable over a 500 m stratigraphic thickness, and the mine sequence mineralised gneiss. It was recognized that the overall style of mineralisation at Walparuta is clearly stratabound, being directly related to introduced and remobilized magnetite which is abundant in the now brecciated quartzitic gneiss and in related vein stockworks. Accordingly, it was proposed to drill two RC holes to test both near and along strike from the former main copper-gold workings, targeting the centres of major magnetic anomalies evident within the mineralised gneiss. A secondary programme, of 53 RAB drillholes along two traverses across the Walter Outalpa prospect grid, was designed to test for bedrock gold anomalism away from the known mineralised shear zone. During September 1991, Placer Exploration actually completed 3 RC drillholes at Walparuta, for a total penetration of 446 m. The best mineralised drillhole intercept obtained near the old main workings was 2 m @ 0.6% Cu and 1.15 g/t Au, from within the wider depth interval 58-86 m in hole WP01 that averaged 0.25% Cu and 0.4 g/t Au. The drilling results that came from hole WP02 put in further away along strike were disappointing, though, with the best grade obtained there being 0.17% Cu and 1.15 g/t Au from the narrow depth interval 114-116 m. The extra hole, WP03, was drilled to test an EM anomaly, but it failed to encounter the banded magnetite gneiss, and recorded no significant downhole sample assay values. The 350 m of RAB drilling carried out during the same month at Walter Outalpa prospect penetrated bedrock consisting of tonalite gneiss plus minor pegmatite veins, with biotite schist occupying the shear zone. Only low level copper and gold values were returned, the latter being mainly around 15 ppb Au, rising to 60 ppb in more magnetite-rich parts of the shear zone. Over the succeeding eighteen months Placer Exploration conducted follow-up surface drainage geochemical sampling for a suite of pathfinder metals to evaluate previously detected anomalies in four localities. The company also flew colour aerial photographic sorties at 1:25,000 scale across the entire licence area, leading to the preparation of a consultant's photogeological interpretation report. Although further anomalous gold and copper samples were identified near major structural features, Placer eventually decided that the overall prospectivity for finding an economic, large tonnage, ironstone-hosted Au-Cu deposit in the Weekeroo Inlier that might be similar to the Starra - Trough Tank discoveries recently made in Queensland was now much diminished, and accordingly in August 1993 it chose to leave the EL 1507 joint venture. No other field work by the remaining licensees took place before the renewal of tenure as EL 1854 in that same month, nor during the following year under a new joint venture agreement made with Eyre Resources NL, principally because of uncertainties regarding the likely application of Commonwealth Native Title legislation to pastoral lands.