North Ltd's Barton Project commenced in 1990 across a number of licences progressively taken out over the western Gawler Craton, which eventually came to include EL 1865. Initial exploration for heavy mineral sand in the Barton-Ooldea area, 100-200 km north of Fowlers Bay, comprised reconnaissance sampling, a photogeologic survey and RC drilling (695 holes, total 24 128 m). Zones locally enriched in zircon, ilmenite and leucoxene were located, but their overall grade and volume were insufficient for economic mining. Results of drilling a further 55 holes (total 1168 m) on EL 1717 were released in 1992. A shift in focus to Ni, Au and PGE exploration began with petrology on basement samples from the sand drilling, followed by ground magnetics and aircore drilling (65 holes, total 2997 m; none within EL 1865). Copper intersections peaked at 468 ppm Cu from 12 to 26 m in weathered, quartz-veined amphibolite (in hole BAC43 drilled on EL 1602). The final phase of exploration, which principally involved work within EL 1865, targeted copper and gold associated with Hiltaba Suite intrusives. No significant values were returned from initial geochemical sampling of basement outcrops and existing drill collars. Aircore drilling of aeromagnetic anomalies on the northwestern and northern margins of the Mitcherie Pluton (34 holes, total 2818 m) intersected brecciated monzogranite to syenogranite with haematitic, chloritic, magnetitic, epidote and sericitic alteration displaying weakly anomalous copper. Minor anomalous gold and nickel were returned from aircored calcrete and basement samples, and also in augered calcrete samples. A low-level aeromagnetic survey was followed by further aircore drilling of the northern margin of the pluton and associated structural targets (74 holes, total 5350 m). Neither significant alteration nor coherent anomalism were detected. Depth to weathered basement was commonly excessive, particularly over major shear zones, and the regolith below the upper calcareous dune system was found to be non-calcareous.