1. University of Botswana, Geology Department, Private Bag UB 00704, Gaborone, Botswana e-mail: mapeorbm@ub.ac.abw
2. Kalahari Key Mineral Exploration Company (Pty) Ltd, PO Box 405239, Broadhurst, Gaborone, Botswana e-mail: kalaharikey@gmail.com; andy.moore.bots@googlemail.com
3. School of Earth, Atmosphere and Environment, Monash University, Melbourne, Victoria 3800, Australia University of Melbourne, Australia e-mail: jack.mulder@monash.edu
4. School of Earth and Environmental Sciences, The University of St Andrews, St Andrews KY16 9AL, United Kingdom e-mail: nick.gardiner@st-andrews.ac.uk
5. Oxford University, Department of Earth Sciences, South Parks Road, Oxford OX1 3AN, United Kingdom DSI-NRF Centre of Excellence, University of Johannesburg, South Africa e-mail: laurence.robb@earth.ox.ac.uk