Four Mineral Claims of 40 acres each were taken out by Kennecott in October 1967 to allow investigation of a major fault breccia and fracture zone in Proterozoic rocks in the Yudnamutana area of the northern Flinders Ranges. The intention was to test this one of many similar occurrences of low grade secondary copper mineralisation that exist as extensive developments of malachite staining and limonite gossans within major fault zones in the Mount Painter district. Initial surface sampling and mapping of the target Jubilee Fault zone outlined an area of the order of 200 feet wide and 4,000 feet long of fractured rock containing 0.2% Cu at surface. A previous reconnaissance IP survey had indicated the presence of some sulphides associated with the fault at shallow and medium depths. The initial appraisal by Kennecott of the surface expression of mineralisation suggested that the copper content of the near surface rock was depleted with respect to the likely primary grade for two reasons: (a) The formation of a siliceous surface skin by weathering has masked the true copper content of the oxidised zone. (b) The oxidised zone itself has undergone leaching. A 12-hole programme of angled percussion drilling to 200 foot driller's depths was then carried out to further test the oxidised zone for copper content and to evaluate its relationship to the primary zone. The results overall gave an average of only slightly better than 0.2% Cu, although lenses of higher grade up to 1% Cu were common. The holes were drilled in 2 areas to test a total strike length of 1200 feet, a width of 200 feet and a vertical depth of 173 feet. The deep primary zone was then tested near the abandoned Old Noll mine by one diamond hole drilled to 601 feet driller's depth, which was directed at 60 degrees inclination to intersect the fault breccia and shear planes below the oxidised zone at a place where percussion drilling had averaged 0.48% Cu over a 180 foot width. This diamond hole revealed sulphides consisting of 2% - 4% pyrite only, containing a mere 380 ppm Cu over 45 feet. Thus the actual full drilled 200 feet width of the fault breccia plus fractures and shears averages just 240 ppm Cu, which is 1/20th of the grade seen in the overlying oxidised zone. Therefore, in view of the substantial copper enrichment that has taken place in the oxidised zone, it would seem that the Yudnamutana area has undergone a complex weathering history not initially suspected. It appears that during a previous weathering cycle, leaching took place leading to the formation of a buried secondary enrichment zone. Subsequent lowering of the water table and continued erosion then led to the oxidation of this secondary enrichment zone and eventual exposure of the upgraded oxidised zone at the surface, to give a misleading surface capping. From consideration of these results it is deemed unlikely that economic copper orebodies are present in the primary zone of the Jubilee Fault breccia and fracture complex. However, it is possible that small bodies of mineable grade may exist in tension gashes beneath high grade carbonate lodes at the Sir Dominick mine.