This volume of the Journal recognizes the immense contribution of Professor Dick Minnitt, of the School of Mining Engineering at the University of the Witwatersrand (Wits), where he is one of their four NRF-rated academics and one of only three Professor Emeritus appointments in the School. He spent most of his career at Wits, supervising not only postgraduate (MSc/PhD) candidates and publishing his own research, but also presenting courses in geostatistics and mineral economics for mining investment in his specialized fields of mineral economics and mineral resource evaluation. Over the years he not only materially contributed to, but also supported and maintained a close association with, the Southern African Institute of Mining and Metallurgy (SAIMM). Though ‘retired’, he continues to provide valuable insights and inputs for ongoing mineral resource research to both industry and academia.

Professor Dick Minnitt

Professor Minnitt was appointed as the JCI Professor of Mineral Resources and Reserves in 2001, and over the years has received many merit awards, including three silver medals from the SAIMM in 2008, 2014, and 2016, and most recently the Pierre Gy Sampling Gold Medal in 2017, awarded for excellence in teaching and application of the Theory of Sampling by the World Conference in Sampling and Blending, at the Eighth World Conference on Sampling and Blending 2017. He is a Fellow of the SAIMM, a Fellow of the AusIMM and the Geological Society of South Africa (GSSA), and a life member and past president of the Geostatistical Association of South Africa (GASA). His accolades, awards, and contributions are indeed numerous, illustrating both dedication and much sacrifice of his private life, yet he still finds time to go above and beyond, as shown in 2016 through his membership of the organizing committee for the 35th International Geological Conference.

Professor Minnitt has published some 65 technical papers both locally and overseas. The variety and diversity of his contributions to research and industry as reflected in this Journal, deserves mention, from aspects that include mine planning (36%), geology and resource estimation (21%), government and mining policy (21%), to technology, metallurgy, and environmental papers that make up the final 22% of this volume. Most of the contributions are from Wits University, showcasing ongoing research at Wits, with the balance of the papers from industry.

Mine planning aspects cover subjects including stochastic cut-off grade derivation aimed at quantifying uncertainty with regards to input parameters for cut-off grade modelling, assessment of modifying factors for reserve declaration, and spatial mine planning reconciliation. The latter provides possible solutions to the practitioners’ challenge with regards to long-term/life-of-mine versus short-term spatial mine reconciliation and compliance.

This volume also highlights how geology and resource modelling underpin economic block modelling and demonstrates how stochastic processes, which quantify uncertainty pertaining to geology and economic parameters, could reduce the risks in resource/reserve and mine financial evaluation. The geology and resource modelling papers further show the advantages of accessing additional information for geological modelling, including resistivity data for manganese resource modelling and reflectance spectroscopy for mapping hydrothermal minerals.

The policy papers present some interesting contributions including an evaluation of government participation in the mineral sector in Tanzania and South Africa, as well as the role of women in the mining sector. The technology, metallurgy, and environmental topics range from the use of unmanned aircraft systems for highwall mapping in open pits to environmental dust controls.

It is hoped that readers will benefit from this volume, which recognizes the immense contributions that Professor Dick Minnitt has made to both research and industry.

W. Assibey-Bonsu
Group Geostatistician and Evaluator, Gold Fields Limited