Late Pleistocene scaphopod beads from Boodie Cave and deep time traditions of personal ornamentation in northwest Australia

Tubular segments of Scaphopoda (tusk shell) were traditionally used by Aboriginal peoples in the manufacture of ornate bead necklaces across northwest Australia. Twenty-seven scaphopod shell beads were recovered from Boodie Cave on Barrow Island dating to between 13,500 and 10,600 cal BP. We compare the Boodie Cave bead assemblage to historical necklace collections as well as experimental studies on scaphopod blanks to characterise bead manufacture, breakage, use-wear, and placement patterns. Results demonstrate that the Boodie Cave beads are larger than other northwest Australian collections; have been manufactured by an anvil-rested percussion technique; have signs of use-wear in the form of polish and rounding but are less curated than specimens from the inland Kimberley. The use-wear study identified that the Boodie Cave beads were strung in a series in a pattern not observed in historical scaphopod necklaces from northern Australia. This patterning may represent a regional variation in display and technological organisation and was likely part of wider ornamental practices documented in historical sources. In all, the Boodie Cave beads provide early and additional evidence for the trade, wearing, and loss of scaphopod beads by mobile hunter-gathers on a dynamic coastline.