Beads and bead residues as windows to past behaviours and taphonomy: a case study from Grassridge Rockshelter, Eastern Cape, South Africa

Ostrich eggshell and gastropod shell beads provide important evidence for understanding how past peoples decorated and cultured their bodies and may also be used as proxy evidence for interpreting the nature and extent of past social networks. This study focuses on the ostrich eggshell and gastropod shell bead assemblages from the terminal Pleistocene (~ 13.5 to 11.6 ka) and mid-Holocene (~ 7.3 to 6.7 ka) occupations from Grassridge Rockshelter, South Africa. We present results from a multi-method approach to understanding bead manufacture and use that combines a technological analysis of the bead assemblages with Raman spectroscopy. Raman spectroscopy analyses were conducted on surface residues identified on the beads, ochre pieces, a grooved stone, and sediment samples, and provide further insight into past behaviours and taphonomy, as well as modern contaminants. Results indicate that ostrich eggshell beads were manufactured at Grassridge during both occupations, and that bead size changed through time. Use-wear and residue analyses demonstrate the complex taphonomy associated with bead studies from archaeological contexts, and the need for further taphonomic research. These analyses also suggest that some ostrich eggshell and Nassarius beads were potentially worn against ochred surfaces, such as skin or hide, as evidenced by the amount and location of the ochreous residues identified on the beads.