Toki (adze) and pick production during peak moai (statue) manufacture: geochemical and radiometric analyses reveal prehistoric provenance, timing and use of Easter Island's fine-grain basalt resources

Pacific and Rapa Nui (Easter Island) volcanologists, geologists, and geochemists have set the stage for archaeological lithic sourcing studies by providing practical data regarding the island's geodynamic activity, geomorphological formation and dating, and the macroscopic, microscopic, and elemental proprieties of Easter Island stone. Drawing upon this information, and the research collaboration between two active archaeological projects on Rapa Nui - the Easter Island Statue Project and the Rapa Nui Geochemical Project - we trace the prehistoric transfer of basalt resources from the Ava o'Kiri and Pu Tokitoki quarry complexes to the moai (statue) quarry at Rano Raraku between AD 1455-1645. Our conclusions better highlight socio-political and economic interaction during Rapa Nui prehistory, while delineating the relationship between adze and pick production and moai manufacture. In this article, we report: 1) a synthesis of a five-meter deep field excavation of moai RR-001-156 in Rano Raraku; 2) a C-14 assessment which dates human presence around moai RR-001-156; 3) 31 basalt quarry and source site descriptions; and 4) archaeometric data using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and principal component analyses of 21 archaeological and 117 geological samples