THE ROLE OF COPPER SMELTING IN THE PRECOLONIAL EXPLOITATION OF THE ROOIBERG TIN FIELD

Two arsenical copper artefacts, found at Rooiberg in the northern Tran svaal, have been analysed by instrumental neutron activation analysis and particle-induced X-ray emission. The results are presented and the compositions are compared with earlier reports. Dating of charcoal in clusions in one of the artefacts by accelerator mass spectrometry plac es its manufacture between the 11th and 13th century AD, in comparison with the period between the 15th and 17th century AD for a tin artefa ct from the same area. Possible palaeo-metallurgical smelting techniqu es are considered in relation to the probable mineralogy of the copper , arsenic and tin in these ore deposits. The evidence is consistent wi th indigenous discovery of tin metallurgy from copper or iron producti on. Rooiberg most likely supplied tin to the Zimbabwe culture area dur ing the Zimbabwe period and perhaps as early as the K2 and Mapungubwe periods.