Uranium occurrences have now been found over extensive areas of outcropping Archaean granitoid rocks and migmatites in the Crocker well area, approximately 40 miles north-west of Olary in the north-east of South Australia. The South Australian Government Mines Department commenced mineral exploration in this area in December, 1951, following the discovery of uraniferous deposits by an airborne scintillometer survey, and since that time the interest in the area as a source of uranium and rare earth minerals has gradually expanded. An extensive ground prospecting survey of the district surrounding the original Crocker well deposit was initiated in October, 1953. This report contains a complete record of the surface mineral occurrences found up to 2/2/54, during a period of about three months field work. It also contains detailed notes on the nature of uranium mineralisation in the area.