In Pacminex' adjoining Cleve EL 667, a lead-zinc mineralised basement stratum lies parallel to a characteristic linear aeromagnetic trend. Within the subject EL 666 to the south, the Butler Tanks and Mount Hill aeromagnetic trends were suspected to be reflections of synclinally folded equivalent geological strata, and so they were geochemically sampled to look for similar base metal anomalism. Weak such anomalism was detected in soil samples taken from 3.2 km south of Mount Hill railway siding, but the subsequent drilling to bedrock there of 72 auger holes only yielded assay maxima of 640 ppm Cu, 1800 ppm Pb and 710 ppm Zn from mica schist beneath a substantial calcrete capping. This result was interpreted to indicate only a low mineralisation potential in comparison to that of the Cleve area, and so the decision was made to surrender the exploration lease.