An area centred 33 km south-east of Nackara was taken up by CRA Exploration (CRAE) when the company's prior surface reconnaissance geochemical sampling had yielded picroilmenite grains (a kimberlite indicator mineral) in the vicinity of where Stockdale Prospecting Ltd had earlier reported finding 32 detrital microdiamonds. The tenement is mostly covered by Quaternary alluvium and low angle slope deposits. Topographic highs consist of Adelaidean metasediments. High level, silcreted Tertiary gravel deposits occur in the north-east. Regional gravel sampling for heavy mineral kimberlite indicators, plus the acquisition of part of a regional airborne magnetic/radiometric survey flown along east-west flight lines spaced 250 m apart, aerial orthophoto photo-interpretation, and a re-interpretation of data from the 1979 Peterborough aeromagnetic survey, were followed-up in 29 selected locations by the conduct of ground magnetic surveys, outcrop rock chip, grid-based soil, and gravel bulk sampling along drainage features, re-sampling of stored bedrock drill cuttings of previous BHP holes for petrological examination, and new exploratory shallow RC drilling during November 1985 (21 holes totalling 392.5 m) of potential kimberlite targets. One 0.65 mm x 0.30 mm microdiamond crystal, plus pyrope, picroilmenite, chromite and zircon heavy mineral grains were recovered from a 100 kg bulk loam sample collected over an indicator anomaly site near Mackys Dam, but no diamonds or kimberlite were found there or elsewhere by CRAE's RC drillholes, which all ended in buried ?Adelaidean sedimentary bedrock units of low metamorphic grade. Hole 85CBRC16 was terminated at 27 m depth after drilling 1 m into a dolerite dyke, the likely source of aeromagnetic anomaly CB26. Nevertheless, heavy mineral sampling of the thin layer of cover material encountered above bedrock at several aeromagnetic anomalies yielded fresh kimberlite indicator minerals, suggesting proximity to a kimberlite source. A kimberlite was described from a bottomhole sample taken in previous BHP drilling of its aeromagnetic Anomaly 30 [but this part of the submitted petrological data was stolen/lost before SADME had done the preservation microfilming of the EL 1249 first quarterly report]. CRAE's on ground follow-up of aeromagnetic and photogeological features encountered outcropping basic igneous volcanic and sub-volcanic rocks in three instances (at anomalies CBP13, CB18 and CB19).