The kula is a famous exchange circuit linking some of the islands off the eastern tip of Papua New Guinea. In his classic ethnography, Bronislaw Malinowski (1922) describes how the two most highly ranked valuables were exchanged. In 1915-18, these valuables were Conus armshells and shell bead necklaces, but in 1855 this was not the case. When prehistory merged into history on Woodlark Island, it was circular boar's tusks rather than Conus armshells that were exchanged for shell necklaces. To understand how one prime valuable replaced another, it was necessary to look more broadly at changes in kula valuables since 1855. The study covers circular boar's tusks, Conus armshells, shell bead necklaces and ceremonial stone axes. Assemblages of these artefacts were assembled from examples in museum collections, historical photographs and documents. While Malinowski's ethnography captured the kula as it operated in 1915-18, this study demonstrates that it has been a constantly evolving exchange system.