Annual report, EL 3059, Point Stuart

Abstract

EL 3059 is held by AGIP, originally to explore for uranium. The thickness of cover was prohibitive to a uranium search. Recent upsurge in the demand for lime resulted in a change of exploration emphasis to explore the potential of shell grit and lime sand deposits. The shell grit in the area was previously auger drilled by Northern Cement under EL 931 in the early to mid 1970s. Their work and photointerpretation suggests that lime sands and shell ridges existed up to 10 km inland. AGIP undertook auger drilling and bulk sampling. Five bulk samples of coast deposits and from Sampan Creek were assayed at the Department of Mines and Energy. After riffling, samples were subject to dry and wet screening tests. The coarser the material, the the higher the CaCO3 content and lower SiO2. The average grade of the five samples varies between 62% to 78% CaCO3 with negligible MgCO3, Fe2O3 and Al2O3. The SiO2 content varies between 21.2% to 24.8%. The high SiO2 could be dealt with by washing. The split at 500 microns recovers 64% of the total CaCO3 at an average grade of 91.77% CaCO3 and 5.68% SiO2. Additional samples were taken and resource estimates for insitu resources and possible extractable shell grit and CaO are presented. A total resource of 4,484,446 t of shell grit containing 1,805,095 t CaO was determined. Of this 1,345,334 t of shell grit was deemed extractable for 541,529 t CaO all with an average grade of 40.25% CaO. A Landsat image was processed to enhance bands that would show target minerals. While the image enhancement clearly outlined dunes and palaeo-dunes it could not distinguish shell grit and lime sand form other Quaternary sediments.