Renewed exploration by E-Z of the area surrounding the Beltana zinc mine has investigated the possibility for finding deep, unweathered Cambrian or Proterozoic carbonate-hosted zinc-lead sulphide mineralisation. It was considered that this target had not been adequately addressed in the company's previous work, despite the extensive diamond and percussion drilling done to evaluate the fault-related willemite orebodies. The major part of the new work programme was taken up with very detailed geological mapping and geochemical sampling of the base metal - anomalous host rocks to the ore deposits, and also their alteration haloes, plus comprehensive geochemical sampling of bedrock through new RAB drilling (99 holes, total 893 m) and by analysing stored samples from previous drillholes, including ETSA water bores, as a way to detect possible additional willemite or primary ore occurrences concealed under alluvial cover. Much effort was put into delineating structures within outcropping bedrock, and their effects on original rock textures and spatial relationships, particularly with regard to the influence of diapirism on sediment diagenesis and ore emplacement. A single diamond hole was drilled to 380 m within ML 4369 to test the significance of a geochemical anomaly seen along the Ajax Fault near the Ajax South copper mine, but only rare pyrite, sphalerite and chalcopyrite grains were found in dolomitised limestone. Later activity comprised a large trial of time-domain dipole-dipole IP surveying and follow-up percussion drilling (7 holes, total 589 m) to test certain geochemical anomalies related to the Norwest Fault, but only low grade zinc intersections were recorded from under the cover. Due to lack of success in identifying further ore reserves, the licence was surrendered in late 1987 when a major overseas zinc market customer, Preussag AG of Germany, declined to place any new orders for its share of ore concentrate production from the existing Beltana mine.