Bennett, W & Fowler, A 2022, 'Assessing the reasonable prospects for eventual economic extraction of a caving project', in Y Potvin (ed.), Caving 2022: Proceedings of the Fifth International Conference on Block and Sublevel Caving
, Australian Centre for Geomechanics, Perth, pp. 331-342, https://doi.org/10.36487/ACG_repo/2205_22
As the rigour required for mineral resource reporting increases, criteria for ‘reasonable prospects for eventual economic extraction’ (RPEEE) are becoming more common in the industry and are an explicit requirement in some reporting jurisdictions. These criteria require an assessment of the mineral’s potential price, its processing characteristics and mining factors including the mineral’s concentration and the deposit's geometry. For near-surface deposits, which are likely to be mined as open pits or high grade deep deposits to be mined using underground selective methods, this assessment is relatively straightforward. However, for mining massive deep deposits, it is more complex.
This paper discusses the complexities of defining RPEEE when an underground caving method is expected and describes an approach and a brief application case developed by the authors for assessing what material can be reported as a resource under these criteria. The paper should be of interest to geological professionals who are preparing resource statements, and financial and mining professionals who are evaluating the reserve and economic potential of those resources.
Keywords: reasonable prospects for eventual economic extraction, RPEEE, caving
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