*This is an abstract only. No full paper is available for this abstract.* The Tropicana discovery, located 330 km north-east of Kalgoorlie and 300 km east of Laverton, Western Australia, is a new deposit style in a previously unrecognised and unexplored gold province. Tropicana is an unincorporated joint venture between AngloGold Ashanti Australia Limited (70 per cent) and Independence Group NL (30 per cent). AngloGold Ashanti is the manager of the joint venture. This paper gives a brief overview of geological context and sets out the approach taken for the Resource estimate, including the logic of selecting the estimation method employed, the use of geological knowledge to determine domains and the technical steps in generating and then validating the estimate._x000D_
The Tropicana deposit has a known strike length of approximately 5 km and defines a north east trending mineralised corridor approximately 1.2 km wide. The mineralisation comprises four distinct structural domains; from north to south these are Boston Shaker, Tropicana, Havana and Havana South zones. The deposit is located within a more strike-extensive mineralised system, which extends for at least 10 km._x000D_
The four structural domains are effectively the same mineralisation off-set by east to north-east striking, post mineralisation faulting. The mineralised zones within the four domains are principally hosted within rocks of quartzofeldspathic gneissic associations and are known as the favourable horizon'. The favourable horizon is underlain by a mixed stratigraphic package comprising rocks of the quartzofeldspathic gneiss, garnet gneiss, granulite and amphibolite associations. The top of the footwall package is taken as the first appearance of garnet gneiss, amphibolite or granulite._x000D_
The project has benefitted from continuity of key senior personnel in a time of flux in the mining industry; this has enabled the understanding of the deposit and geological model to evolve and develop as further drilling extended the known mineralisation. Rigorous data validation and quality control procedures on inputs give confidence in the Mineral Resource estimate._x000D_
The open pit Mineral Resource estimate was completed using uniform conditioning, a non linear geostatistical estimation method. A number of alternative comparative models were created during the Tropicana Feasibility Studies and have largely confirmed the estimated grade of the deposit. Importantly, a program of close-spaced grade control drilling was completed as part of the Feasibility Study, which allowed for validation of the Mineral Resource estimate, optimal grade control drilling strategies and mining selectivity studies._x000D_
The Tropicana Gold Project was approved for development by the boards of AngloGold Ashanti Australia and Independence Group in November 2010, based on a Bankable Feasibility Study into the viability of open pit mining and carbon-in-leach processing at a nominal fresh-rock throughput of 5.8 Mt/a. Since that time, additional reserves have been added at Boston Shaker and the additional mining area has been incorporated into the overall life-of-mine plan._x000D_
CITATION: Kent, M, Catto, B, Doyle, M, Gibbs, D, Matheson, M, Singer, R, Kendall, B and Vann, J E, 2014. Tropicana Gold Mine, Western Australia - a case study of non-linear mineral resource estimation, in Proceedings Ninth International Mining Geology Conference 2014, pp 189-190 (The Australasian Institute of Mining and Metallurgy: Melbourne).