A small exploration licence area centred approximately 60 km west-northwest of Whyalla, which is mainly covered by Quaternary sediments, has been taken up by the South Australian Iron Ore Group Pty Ltd(SAIOG), a subsidiary of WA-based Portman Iron Ore Ltd, to explore for possible concealed economic deposits of iron ores similar to those mined in the Precambrian rocks of the nearby Middleback Range. All of the mineral exploration licences held by SAIOG were transferred to Centrex Metals Ltd under an agreement that was reached in late 2003. The exploration target units of Banded Iron Formations (BIF) form part of an extensive early Proterozoic BIF sequence belonging to the Middleback Subgroup of the Hutchison Group. A prominent south-west trending outcrop of Lower Middleback Jaspilite BIF forms the South Camel Hills situated on the eastern boundary of the licence area, and is associated with a prominent linear magnetic anomaly in regional magnetic data which was thought to perhaps denote the presence of magnetite iron ore. Potential was also seen by Portman and Centrex for discovering buried haematite mineralisation, similar to that mined 30 km to the south-east at Iron Duke on the southern end of the Middleback Range, in nearby flanking locations where continuations of BIF strata may underlie Tertiary to Recent cover. During the first licence year, the following exploration programme was completed: - acquisition of a detailed, grid-based ground gravity survey in two field sorties by the contractor, October-November 2002 and January 2003, for a total of 2625 stations read on EL 3018 on two 200 m x 50 m grids located in the SE part of the licence; - exploratory drilling of 4 vertical RC holes with a total penetration of 378 m on the discrete 1 mGal Kimba Gap gravity anomaly; - performing ICP Fusion OES method whole rock assays, plus ARM2 method base metal / gold pathfinder suite assays, on 40 drill cuttings samples taken from hole KMRC002; - commissioning the petrographic examination of drill cuttings from holes KMRC002 and KMRC004; and - making in-field specific gravity determinations on several samples of fresh drill cuttings. The gravity surveys defined a discrete gravity anomaly lying in a covered area off the southern end of the South Camel Hills, and the prognosed dense source to this anomaly at a depth of 80 to 100 m was targeted by the drilling. Beneath 13 to 24 m thick Tertiary cover, the RC drillholes encountered a bedrock basement suite of fresh mafic/ultramafic rocks ranging in lithology from feldspathic hornblendite or metapyroxenite to hornblende-gabbro or metagabbro. The deepest drillhole, KMRC002 sited on the peak of the gravity feature, encountered a very biotite-rich lamprophyric rock persisting down to its TD of 150 m. The simple density determinations returned an average SG of 2.9 for this mafic rock. Subsequent remodelling of the gravity data based on the SG determinations, allowing for a density contrast of 0.25 between gabbroic rocks and enclosing granitic gneisses, returned an anomaly shape which closely resembled the observed gravity data, therefore implying that the mafic suite is the probable source of the gravity anomaly. A possibility remains for the gravity anomaly source to be a very large dense body (e.g. an IOCG deposit or iron ore deposit) positioned at >150 m depth. These holes were considered to have adequately tested the shallow hematite concept. No anomalous gold or base metal assay values were returned. During licence Year 2, after Centrex took ownership of the licence, no field work was done. A joint venture agreement was set up with Kanowna Lights NL, who did a desktop assessment of the area's gold and base metal potential. Again during licence Year 3, no field work was done, but a number of prospectivity technical reports were prepared for the Middleback Project as a whole based on consultants' analyses of geological, geophysical and structural data and their observations made on field visits. It appeared that the geophysical responses of BIF and the physical continuity of such strata have been greatly affected by faulting and weathering, to complicate their mapping in the subsurface. During licence Year 4, no field work was done, but existing regional aeromagnetic data was reprocessed and imaged by a consultant. Plans were made to fly a detailed airborne magnetic/radiometric/DTM survey over several Centrex tenements in the western Middleback region, followed by the acquisition of ground gravity surveys and palaeodrainage analysis (for the assessment of detrital iron ore potential).