Orogenic Exploration Pty Ltd

Shell Lagoon Diamond Project (Surrendered)

The Shell Lagoon tenement covers an area of 698 square kilometres, located northwest of Woomera, South Australia. The area is located within the Woomera Instrument Range which is part of the Woomera Prohibited Area. The primary objective of all the exploration has been diamonds.

Previous diamond exploration was conducted by CRA Exploration Pty Ltd under EL1837 and EL1839 between 1993 and 1996. Within these two tenements, a total of 80 heavy mineral samples were collected, with 39 samples positive for kimberlitic indicator mineral gains. Over 1400 chromites, 11 pyrope, 5 picroilmenite and two microdiamonds were recovered by CRAE from these samples. Detailed aeromagnetics were also flown over the area by CRAE. A couple of the selected magnetic targets outside of the current area of EL2785 were drilled by CRAE, but proved negative for kimberlites. CRAE eventually concluded the grains were secondary sourced, but proximal, and abandoned the project in 1996.

In early January 2002 the available open file aerial geophysical data was examined by Orogenic's consulting geophysicist and a number of new magnetic targets were selected as possible kimberlitic targets.

Twenty nine (29) heavy mineral samples for indicator mineral examination, weighing a total of 805kg have been collected from the current tenement area in two separate sampling programs by Orogneic.

The first sampling program by Orogenic was a series of seventeen heavy mineral loam and stream samples (SL-01 to SL-17) collected in December 2002, and totalling 501 kg. These samples were processed in Perth, then examined for kimberlitic indicator minerals by Dynamic Mineralogical Services. The aim of the sampling was to test the discrete magnetic anomalies provided by the consulting geophysicist. Three samples (SL-08, SL-09, and SL-10) along Mungappie Creek containing 92 very interesting chromites.

A total of twelve stream heavy mineral loam samples (SL-18 to SL-29) were collected from the Mungappie Creek drainage area in September 2003. A representative of the Kokatha Land Council checked and approved each site, and supervised every sample collected, as this creek contains a large number of significant aboriginal cultural sites. Total material shipped to Perth was 304 kg. These samples were processed in Perth and preliminary results for some samples have been received from Dynamic Mineralogical Services, indicating that high counts of chromites were again recovered in some samples.

On the 20 December 2004 Orogenic Exploration was notified by the laboratory that a small diamond had been recovered from sample SL-22 in the +0.4mm fraction. This sample is along a small dry tributary on Mungappie Creek. The size of the pale greenish dodecahedral diamond recovered is 0.55 x 0.45 x 0.35 mm, with a weight of 0.0015ct.

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In April 2007 Orogenic Exploration Pty Ltd entered into a JV agreement with Venture Minerals Limited as part of their Churchill Dam Project. This allowed Venture Minerals to earn 90% interest in the non-diamonds rights of the Exploration Licence. The chemical and morphological quality of kimberlitic indicator minerals recovered is extremely encouraging, with good chromite, and one small diamond now recovered. The recovery of a diamond confirms the interpretation of the numerous chromites found in this drainage as having diamond association chemical signatures. Further sampling was planned to investigate further but access issues associated with the Department of Defence resulted in the Exploration Licence being surrendered.