Evaluation of known Tertiary sedimentary diatomite occurrences in the central Murray Mallee was carried out by Agricola Mining Pty Ltd on three prospects located near Geranium. Rotary drilling, with variable recovery sections of bottomhole diamond core cut in some holes (for a total of 75 holes aggregating 393 m), indicated the existence of a resource of approximately 200 000 tonnes at the Mintabie Homestead prospect, but oil and water absorption testing of samples taken from all three occurrences showed the diatomite to be of relatively poor grade. Under a joint venture agreement that was in place between August 1998 and January 2001, Redfire Resources NL concurrently explored the licence for Tertiary heavy mineral sands marine placer deposits. Air core drilling of two buried Pliocene coastal strandlines along four short traverses (31 holes, 901 m) encountered widespread Loxton/Parilla Sand, with a best intersection of 3 m @ 3.19% heavy minerals from 15 m depth.