The Edinburgh Geologist
Ancient mining in Swaziland
by Bill Baird
Iron ore in its various forms is a major mineral resource in Southern Africa. When Europeans first visited the area around Postmasburg in the Northern Cape around 1800 they found various sites where mining of red ochre and specularite had taken place. Local people such as the Tswana and Hottentots were familiar with these workings but mostly they attributed the tunnels and shafts to the 'old people', the Khoisan. Some of these tunnels extended over 100 metres underground and into areas where specularite was available. This mineral was more highly prized than either ochre or haematite and could be widely traded with other people who were not fortunate enough to have a source in their area. The mining operations showed a high degree of skill, knowledge and daring.
When prospecting operations were carried out in 1957 in an area known as the Bomvu Ridge in the Ngwenya massif of Swaziland they estimated some 30,000,000 tons of iron with a mean value of 60% metallic iron content. The Swaziland Iron Ore Devolopment Corporation decided to mine the ore body and production started in 1964. The ore was taken by rail to the port of Maputo in Mozambique and from there shipped to Japan.
During the mining so many ancient stone tools were found that the news reached the archaeologist Professor Raymond Dart in South Africa. Dart sent a knowledgeable colleague called Adrien Boshier to investigate these finds and report back. What Boshier found was amazing, specialised stone tools made of dolerite, which is not a local stone, had been left behind by the early miners. These choppers, picks and hammerstones were not just on the surface but also deep underground. It seems that these early miners removed at least 1,200 tons of soft haematite ore rich in specularite from one particular mine, Lion Cavern, alone. The question was how old were these mines? Archaeologist Peter Beaumont was producing evidence which suggested that these mines had been operated in the Iron Age, Late Stone Age and possibly even Middle Stone Age. However, hard evidence was still required in order to put a more precise date on the ancient mines. Then in 1967 charcoal nodules from some of the more ancient adits were sent to Yale and Groningen universities for Carbon 14 testing. The results that came back were astounding, dates of around 41,000 to 43,000 were obtained. Later from another early mine complex the buried skeleton of a child was dated at over 50,000 years.
By 1980 over 20,000,000 tons of high grade haematite had been removed and shipped to Japan and the mining operation was closed down. The mining company had left over a million tons of ore which underlie the ancient mining adit at Lion Cavern. This site is now listed as a national monument and can be visited if one is accompanied by a game ranger from the local Malolotja nature reserve.
If you want to read further, there are many sources including:
Beaumont, P.B., 1973. The ancient pigment mines of Southern Africa, South African Journal of Science, Volume 69, pp. 140-146.
Beaumont, P.B. & Boshier A., 1974. Report on test excavation in a prehistoric pigment mine near Postmasburg, Northern Cape, South African Archaeological Bulletin, Volume 29, pp. 41-59.
Boshier, A., 1965. Ancient Mining of Bomvu Ridge, Scientific South Africa, Volume 2, pp. 317-320.
Boshier, A., 1969. Mining Genesis, Mining Survey, Volume 64, p. 21.
Boshier A. & Beaumont P.B., 1972. Mining in Southern Africa and the emergence of Modern Man, Optima, Johannesburg, 1972.
Boshier, A., 1978. The Earliest Miners, South African Journal of Africana, Volume 1, pp. 9-10.
Cairncross D. & Dixon R., 1995. Minerals of South Africa, The Geological Society of South Africa, Johannesburg, S.A., 1995.
Zaslavsky, C., 1984. The Yoruba Number System in Sertina, I.V. (ed), Blacks in Science Ancient and Modern, New Brunswick, U.S.A., Transaction Books, p. 110.
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