. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . CT D, had a grain size of ASTM 5. It was also not as deformed along itslength as the others, lacked a head, and was probably an unused tack blank. Prills, or cast droplets, were spherical pieces of gold found in diameters from mm to12 mm. They were used to make various items such as punched beads, or flattened intostrips or foil. The casting of these small droplets accounts for the voids or air bubblesnoted by Oddy (1984:73). Larger prills or nodules may have been buttons of goldrecovered from melting crucibles.
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . CT D, had a grain size of ASTM 5. It was also not as deformed along itslength as the others, lacked a head, and was probably an unused tack blank. Prills, or cast droplets, were spherical pieces of gold found in diameters from mm to12 mm. They were used to make various items such as punched beads, or flattened intostrips or foil. The casting of these small droplets accounts for the voids or air bubblesnoted by Oddy (1984:73). Larger prills or nodules may have been buttons of goldrecovered from melting crucibles. The smaller spherical droplets were probably formedby pouring molten gold into water, or melting filings or short pieces of wire in a cruciblepacked with charcoal. Pearson suggested that prills could have been formed by spilling themolten gold onto a flat surface, with the molten gold forming globules as it cooled(Fouche 1937). This untested method appears unlikely given the ease of producing goldshot by pouring molten gold into water. 86 ANNALS OF THE SOUTH AFRICAN MUSEUM. Figure 5 Etched section through a gold tack from Mapungubwe, showing longitudinal cracks running down the length of the shaft and intense cold work deformation in the head (magnification 18x).
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Keywords: ., bookcentury1800, bookdecade1890, booki, booksubjectnaturalhistory
