In an effort to substantiate historical records of >50 diamonds being recovered during pioneer placer gold mining at the Echunga Goldfield, a programme of systematic bulk sampling and gravel depositional mapping has recently been carried out there by the licensees. After completing initial reconnaissance sampling and making heavy mineral studies of one 240 kg gravel bulk sample, six costeans were cut into the basal Tertiary conglomerates that overlie the Late Proterozoic basement unconformity, and 1000 tonnes of gravel were extracted for subsequent treatment through a mobile heavy media separation plant and then a small rotary diamond pan. 1 only microdiamond was recovered, after processing of 75 tonnes, but this find is regarded as enough to authenticate the old reports. A planned continuation of trenching, channel gold sampling and processing of primary gravel bulk samples taken from across all of the old gold diggings was deemed necessary, both to fully evaluate the alluvial diamond potential and to allow an estimation of remaining detrital gold grades and tonnages. As part of a broader regional search for kimberlite diamond sources, 1:2000 scale airphoto interpretation preceded surface drainage stream sediment bulk sampling (99 samples totalling 2000 kg) which failed to locate definitive kimberlitic indicator minerals, although chromites, zircons and medium to high-grade metamorphic heavy minerals such as rutile, staurolite and corundum are relatively abundant and widespread, presumably deriving from weathering of the basal Adelaidean Aldgate Sandstone fluvioclastic metasediments. Fine-grained gold and base metal sulphide detrital particles are also very common in streams in the Echunga district, reflecting a long-lasting and presently still quite active depositional reworking history (streambed detrital gold concentrations generally being <1 g/t Au, and rarely up to 5 g/t). Following the 1979 acquisition and interpretation of data from a 2000 line km semi-detailed airborne magnetic/radiometric survey, a discrete circular 140+ nT aeromagnetic anomaly was delineated at Biggs Flat by consultant geophysical data interpreter Sandy Dodds of Geoex, and was confirmed by ground magnetometer traversing. He thought that this anomaly may represent a possible shallowly-buried, deeply weathered kimberlite pipe, and recommended immediate exploratory drilling. Hand auger soil sampling has since been carried out at two sites overlying the anomaly, and gravity profiling will be commenced shortly. An alternative interpretation of the 1979 aeromagnetic survey data, commissioned earlier from geophysical consultant John Ashley, identified up to 3 subdued magnetic anomalies which might be indicative of buried kimberlite pipes. As well, he too interpreted an intrusive ?ultrabasic igneous body at Biggs Flat, probably occurring at some depth, that he recommended for gravity surveying follow-up to investigate if by chance a Roxby Downs (Olympic Dam) - type base metal mineralised target is present.