No diamonds or kimberlite indicator minerals were found in loam and subsurface samples collected from an area of strongly fractured volcanic rocks in the north-eastern Flinders Ranges, abutting the Lake Frome Plains south-east of Arkaroola. The basalt - associated, secondary deposit of vein-forming vermiculite located in Vermiculite Valley was deemed to be of uneconomic grade, and was also shown to be contaminated with actinolite.