Witwatersrand gold: Discovery matters

Abstract

Descriptions of the Witwatersrand goldfields have invoked superlatives around themes including great wealth, huge depths, giant mines and innovative engineering. After its discovery in 1886 and further discoveries in the 1930s and 1940s, the Witwatersrand dominated world gold peaking at 1000 t Au production in 1970. There has been a steady production decline since 1970, and, although the trend is clear in hindsight, few people predicted the seriousness of the fall in production or the grave situation of the industry today. The annual decline of Witwatersrand production has averaged 20 t of gold per year since 1994; at this rate, Witwatersrand gold mining will end in mid-2022. The forty-year production decline is attributed here to exploration failure as there has been no new goldfield discovered since Evander in 1951. A lesson from many of the world's great goldfields is that, where much gold has been discovered, there remains opportunity for repeats and additions by using new ideas and technologies. Future Witwatersrand exploration could adopt multiple working hypotheses rather than a single exploration model, introduce high-level geoscience training that is appropriate for a range of potential exploration models and strategies, and encourage a mindset in which discovery becomes both imperative for the whole community and an all-guiding passion. New exploration models open new opportunities not considered and tested over the last 60 years.