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ABSTRACT
Copper mining in the Messina area dates back to a couple of centuries, when the indigenous Africans used stone hammers and iron tools to mine the ore. Ancient smelting sites are still visible in the high ridges. However, modern mining dates back to 1906 when the Messina Development Company started mining the copper ore at the Campbell, Harper, Artonvilla, Messina and Spence mines. Since then over 40 million tons of ore were mined, recovering about 700,000 tons of copper. Copper was recovered from chalcopyrite, bornite and chalcocite. Mining stopped in 1992.
The current study of the Messina deposits focused on the geology, geochemistry, mineralogy and structural setting of the deposits. Sulphide mineralisation took place within quartz veins and also as disseminations within amphibolites and metamorphosed limestone. Consequently, two types of ores were established; veined ore and disseminated ore. The deposits appear to lie along a linear profile stretching from east to west. Apparently, the deposits were structurally controlled, thus the structures acted as channel ways for the mineralised hydrothermal solutions. Sulphide mineralisation took place within the crystallizing quartz veins. At the same time, the host rocks were heated up, hence the dissemination of sulphide minerals within amphibolites and metamorphosed limestone.
Geochemical study of soils and sediments in the area confirmed high concentrations of Zn, Cu, As, Ni, Mn and Cr whereas ore samples registered high concentrations of Cu (18.4%) and Mo (43 ppm). The study recommends further detailed work covering ore mineralogy and ore microscopy as well as fluid inclusion geothermometry so as to ascertain the mode of ore formation in the Messina area.
Keywords: Messina copper deposits, geology and geochemistry, structural control, ore mineralogy
INTRODUCTION
Musina formerly known as Messina is situated 8 km south of the Limpopo River, the international boundary between the Republic of South Africa and Zimbabwe. It lies 1 degree north of the Tropic of Capricorn, at an altitude of 633.3 m above sea-level and climate is dry and sub-tropical. The line of rich copper outcrops was originally discovered several hundred years ago and exploited by the "Ancients." Later, those people were overrun by Bantu who took over the workings and produced copper artifacts. In 1903, colonel John P. Gremfell, the founder of the Messina (Transvaal) Development Company...