Implications of petrographic temper analysis for Oceanian prehistory

Petrographic examination of prehistoric Pacific potsherds in thin section a llows robust distinctions to be drawn between indigenous temper sands deriv ed from islands where sherds were collected and exotic temper sands derived from other islands, except that calcareous temper sands of reef detritus a re undiagnostic of origin. Ceramic transfer or movement of ceramic raw mate rials from island to island can be detected because small islands serve as virtual point sources of noncalcareous terrigenous sands, and local island geology is controlled by systematic and well-known geotectonic patterns. Pr ehistoric Oceanian pottery was made locally on multiple islands, rather tha n being dispersed from a discrete number of ceramic centers, but limited ce ramic transfer was widespread within nearly all island groups. As temper an alysis is independent of ceramic typology, sherd tempers in common with obs idian artifacts and other manuports provide unambiguous physical evidence f or migration, trade, or exchange within and between island groups.