An area of the onshore Tertiary Eucla Basin located about 170 km north-west of Ceduna and 50 km north-east of Ooldea Siding on the Trans Australian Railway has been explored for possible economic heavy mineral concentrations formed within shallow marine or shore face sand units of either the Eocene Hampton Formation or the Miocene Ooldea Formation. During June 2007 Rio Tinto flew a regional airborne magnetics and radiometrics survey, termed Paling Range, over most of the subject EL application area before its grant, as part of a much larger survey flown over the company's adjacent ELs 3219, 3220 and 3221. Because there is potential for buried mineral sands in marine beach placer deposits to generate a subtle linear magnetic response from magnetite accumulated within them, Rio Tinto sought such anomalies in the processed aeromagnetic survey data, using a proprietary computerised interpretation programme. Another vector to this type of mineral sands mineralisation, where deposits outcrop, are anomalous radiometric responses from thorium associated with concentrations of the mineral monazite, if present. Therefore Rio Tinto also looked for thorium channel aerial radiometric anomalies of linear outline which might coincide with linear aeromagnetic anomalies, as being indicators of potential mineral sands targets, and several such were identified that the company considered might represent sub-cropping titanium - rich mineral sand occurrences. Late in 2008 Rio Tinto decided to divest its contractual rights to EL 3993. A shortlist of third parties were contacted to tender for the asset. Consequently no field based exploration activities, like follow-up RC drill testing, were undertaken on EL 3993 during the second and third tenure years, while commercial negotiations were progressed with bonafide mineral sand explorers/miners having both the financial and community relations wherewithal to operate in the Maralinga Lands. The entire process was prolonged due to the depressed global economic conditions and poor fund-raising environment for greenfield exploration projects. A favourable bid was received and accepted by Rio Tinto and licensee Wayne Dimech in March 2009; however, the prospective purchaser withdrew its offer in June 2009, citing inability to raise finance. Rio Tinto then re-started sales negotiations with a wider range of candidates, including industrial mineral processers that could be interested in palaeochannel halloysite clay.