Managing Risk in Resource Evaluation
By Dr. Malcolm Lawrence Thurston, P.Geo., Head of Mineral Resource Management, De Beers Group of Companies
Although the tonnage, grade and value of the mineralization does not change, our initial knowledge of these quantities is based on limited sampling. This limited sampling leads to uncertainty in the estimates of volume, density, grade and diamond value (in the case of a kimberlite) and this uncertainty leads to risk in the revenue predicted. In moving a prospect through to a mine, the objective should be to gather data that will reduce the risk to an acceptable level. In the words of King (King et al.,1982): “The general aim of evaluation is to make the result secure against the possibility of substantial surprises”. In other words, mineral resource evaluation should be carried out in such a way that the risk of “substantial surprise” is minimized or at least, that the risk of “surprise” is assessed. In this presentation, I will talk to some of the tools we have at our disposal to reduce and understand evaluation risk. This will be done at the level of the team tasked with carrying out the evaluation and also from a company perspective.
About Dr. Malcolm Lawrence Thurston
Malcolm Thurston holds a BSc degree in Mining Geology, a Diplôme d’Etudes Approndies (option Geostatistics) and a PhD degree in Geostatistics. He has more than 30 years’ experience in the minerals industry with in-depth knowledge of mineral resource estimation in gold, base metals and diamonds. He has worked as a mineral resource consultant outside of De Beers gaining specialized experience in third party auditing. He has work experience in the UK, South Africa, USA and Canada and has travelled to Kimberlites around the world including Southern Africa, Canada and Russia. Malcolm is the Head of Mineral Resource Management for the De Beers Group of Companies and provides guidance and leadership in all aspects of mineral resource estimation.