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Regolith carbonate accumulations are widespread in the southern part of the Australian continent and have been successfully used in the Yilgarn and Gawler cratons as a sample medium in Au exploration. The association of Au with carbonate in regolith profiles has now been established for southeastern Australia, particularly in the semi-arid regions of western New South Wales. This association can be used at both regional and local anomaly scales. Sampling of regolith carbonate accumulations has potential to be an important exploration technique in the region for both Au-only and Au-bearing polymetallic mineralisation. Demonstrated variability in carbonate morphology, mineralogy and chemistry, as well as the landscape setting and aspects of carbonate genesis and dispersion pathways, need to be considered when establishing sampling strategies and regional and local thresholds. It is recommended that a thorough orientation survey be carried out in a region before application of the technique. (C) 1999 Elsevier Science B.V. All rights reserved.