Pre-development feasibility studies of the Mount Hope kaolin deposit, located 75 km north-west from Port Lincoln, gave indications that the kaolin might extend beyond the boundaries of the nine Mineral Leases under which the deposit was held. Accordingly, titleholder the Caledon Resources Group took out an area of about 85 square km as safety acreage surrounding the deposit, within which it could explore for possible lateral extensions to the deposit, or perhaps find separate repeat kaolin occurrences. 10 line km of orientation geophysical surveys, comprising electrical resistivity and EM conductivity methods, were carried out in November 1986, and confirmed the likelihood of lateral extensions. Drilling within the MLs during July 1986 (19 RC holes for 605 m) obtained representative samples for additional testing of the kaolin properties, to determine their lateral and vertical variability within the deposit. This work showed that the kaolin was not of paper coating grade, but might be suitable for paper filler, and possibly also for ceramics. The analyses showed that there is a relationship between the clay slurry viscosity and the contained proportion of minus 2 micron material. However, a relatively low solids content (41.8-55.3%), and the dilatant character of the dispersed clay fines, is a limiting factor for achieving its preferred application as high value paper coating. Reported improvements in the clay rheological properties achieved by previous investigators Robertson Research and Erbsloh GmbH after treating it with hydrochloric acid could not be replicated by Amdel, and pre-treatment by centrifuging was also unsuccessful.