Metal sulphides occurring in dolomitic mud and silt facies (Sweet Nell type deposits) were probably deposited in a supratidal environment, where the dolomitic shale facies with Cu mineralization probably originated closer inshore, while Pb, Zn deposition took place further offshore. The actual controlling factor may have been a rapid change from oxidizing to reducing environments. Higher metal concentrations appear to be associated with local depressions in the post-Pandurra palaeosurface. INPUT surveys to pick up these depressions, followed by drilling, are recommended.