Twin brothers Morris and Richard Viljoen were finally separated on 19 August 2021 when Morris passed away in hospital in Knysna following COVID-19 related complications. He was 81 years old. Born in Johannesburg on 21 July 1940, he, and Richard, enrolled at the University of the Witwatersrand in 1958 where they studied geology. After completing an honours degree at Wits in 1961, Morris was offered a bursary to undertake further studies at Wits in the then recently established Economic Geology Research Unit in the Department of Geology, under the directorship of Professor Desmond Pretorius. Morris was assigned the task of field and structural mapping in the gold-producing district of the Barberton Goldfield and completed an MSc thesis in the vicinity of the New Consort Gold Mine in 1964. For this study he was awarded the Corstorphine Medal of the Geological Society of South Africa and the Captain Scott Medal for the best MSc thesis of the year in any South African university.
Having completed his master’s degree, he joined the Johannesburg Consolidated Investment Company (JCI) in 1963 and was initially involved with exploration of the middle and upper Elsburg gold reefs near Westonaria, which contributed to the establishment of the Cooke Section of Randfontein Estates Gold Mine and the Elsburg Gold Mine. He later undertook field investigations of the Merensky Reef and chromitite horizons in the eastern Bushveld Complex.
In 1965 the twin brothers were offered a Council for Scientific and Industrial Research (CSIR) bursary by the South African Upper Mantle Committee to undertake a project entitled “Ultrabasics in fold belts in the Barberton area,” again under the direction and supervision of Professor Pretorius of the Economic Geology Research Unit at Wits. The research involved a detailed geological, geochemical and economic study of areas in the Barberton region. These investigations, first carried out in the Komati River Valley east of Badplaas, led to Morris being the co-discoverer, with his brother, of a new class of igneous and volcanic rocks which were named “komatiite” after the Komati River. Details of the komatiites have been widely publicised internationally, and a field excursion to the Barberton area to commemorate the komatiite discovery was undertaken in October 2019. A feature article on the Viljoen brothers (and the 50th anniversary of the discovery of komatiite) appeared in the Geobulletin of the Geological Society of South Africa (GSSA) in December 2019 (https://doi.org/10.25131/geobulletin.62.4). Komatiites have subsequently been found in Archaean greenstone belts of all continents and are often associated with major nickel and gold deposits and have, furthermore, shed light on the evolution of the early Earth.
After completing their PhD research the twins were approached in 1969 by JCI to start a Fundamental Geological Research Unit in the company. Morris and his brother began assessing the economic potential of large parts of southern Africa for base and precious metal mineralisation. Between 1969 and 1977 Morris held the position of Senior Research Geologist in JCI and worked on developing geological models for various classes of mineralisation, and target generation for mineral exploration. Areas investigated included the Shangani and Inyati nickel occurrences in Zimbabwe, the Consolidated Murchison antimony–gold occurrences near Gravelotte, and the copper zone deposits associated with the Matchless amphibolites of the Damara Orogenic Belt in Namibia. Extensive travels in southern African countries, as well as worldwide, were aimed at identifying exploration targets for gold, platinum and antimony, and some of the earliest uses of satellite and airborne photographic and thermal imagery were developed by JCI. Morris became an expert at imagery interpretation, including Landsat and airborne thermal infrared imagery, which greatly assisted many JCI exploration programmes.
Between 1977 and 1984 Morris was Consulting Geologist for the Rustenburg Platinum Mines and became involved with the Bushveld Complex. Here he was responsible for geological services to the platinum mines and held the position of Divisional Consulting Geologist – Platinum. Between 1984 and 1991 he was again with the JCI Research Unit and held the position of Divisional Consulting Geologist. In this capacity he was involved with Witwatersrand and non-Witwatersrand gold studies including regional and local target selection as well as detailed modelling of existing mines and exploration areas.
Following his years of association with JCI, Morris was appointed Professor of Mining and Geology at his alma mater, the University of the Witwatersrand, a position he held for 16 years (between 1991 and 2007). Here he taught courses to geology and mining undergraduate and postgraduate students, including courses in photogeology, remote sensing, exploration methods, Earth resource and resource modelling, underground geological mapping, mining geology, mining and the environment, geology ore body modelling, and environmental geoscience. In addition he established a Centre for Applied Mining and Exploration Geology (CAMEG) within the Geology Department at Wits. With his pleasing disposition, his unselfishness and his ability to connect with students and develop their skills, he became an excellent mentor to the many geoscientists and mining engineers he trained during his tenure at Wits. Morris was a firm believer in, and supporter of, field geology and the production of detailed geological maps. He was convinced most geological problems could be resolved by detailed field investigations.
Morris had a close association with the activities of the GSSA, where he served on the Activation, Conservation, Education and Professional Affairs committees and played a leading role in the establishment of the Economic Geology Division of the Society and the Environmental Earth Science Group. He was elected President of the GSSA in 1988. He also received many awards during his career and, with his brother, was the recipient of the Lindgren Award of the Society of Economic Geologists (USA) in 1979. Morris was also awarded the GSSA’s highest award, the Draper Memorial Medal (1985), and the Honours Award (1995), for his many contributions to the earth sciences. He was elected a Fellow of the Royal Society of South Africa, the South African Institute of Mining and Metallurgy, the Geological Society of South Africa and the Society of Economic Geologists.
Morris had a passion for promoting the earth sciences, particularly with regards to geoheritage and geotourism. He led the GSSA initiative of producing a three-dimensional geological model, for the benefit of visitors, which was placed at the cableway terminus on the summit of the Magaliesberg, overlooking the Hartbeespoort Dam. Besides over 80 scientific papers published in peer-reviewed journals, and numerous unpublished company reports, he authored and co-authored a number of books on geoheritage, including An Introduction to South Africa’s Geological and Mining Heritage (co-authored with W.U. Reimold) and Africa’s Top Geological Sites (co-edited with R.P. Viljoen and C.R. Anhaeusser). A book in the final phases of preparation, entitled The Earth–Life Link in the Kruger National Park (co-authored with Kruger Park naturalists) was unfortunately not completed prior to Morris’s death. He also prepared numerous field guidebooks, including Geoheritage of Johannesburg and Central Witwatersrand; Magaliesberg Cableway Guide Book; Geoheritage of Walter Sisulu Botanical Gardens; Mining and Geological Heritage of the Eastern Bushveld; The Eastern Mpumalanga Escarpment; Geoheritage of Southern Kruger Park; Geological Sites of the Garden Route; Swartberg, Meiringspoort and Oudtshoorn Valley; Cape Town, Table Mountain and Peninsula; and Komatiites – 50th Anniversary Field Guide.
Morris furthemore made attempts to promote and publicise the Vredefort World Heritage Site in Parys, and he made significant contributions to the legacy projects of the 35th International Geological Congress held in Cape Town in 2016. He also amassed a large collection of geoheritage-related photographs, maps and publications with the intention of making this material available, particularly for geotourism and educational purposes.
Through CAMEG, and after his retirement from Wits University, Morris together with his brother Richard played an instrumental role in the generation of many exploration targets, several of which have developed into advanced prospects and operating mines. In 2010 he was one of the co-founders of VMIC (VM Investment Company). VMIC laid the foundation for the establishment of Bushveld Minerals and Afritin as fully operational Alternative Investment Market (AIM-listed) mining companies. The geological base on which Bushveld Minerals and Afritin were structured followed from the geological expertise of the twin brothers. Right up until his passing Morris remained a technical advisor to these companies.
Morris remained unmarried for all of his life and retired with his long-term partner Maureen to live at Sedgefield in the Western Cape Province. Maureen sadly passed away a few weeks before Morris, also from COVID-19 related complications. With the passing of Professor Morris Viljoen a huge pillar of the geological fraternity has fallen. He will be sorely missed by family, particularly his twin brother Richard, as well as his many colleagues in geological and mining circles. We may nevertheless take comfort in the fact that memories of Morris will live on in the amazing legacy that he created.