Prehistoric pigment production on Rapa Nui (Easter Island), c. AD 1200–1650: New insights from Vaipú and Poike based on phytoliths, diatoms and¹⁴C dating

Abstract

Although Rapa Nui has been proposed as a classic example of cultural collapse, this hypothesis has been repeatedly questioned. This paper investigates cultural continuity on Rapa Nui following the onset of deforestation through a study of red ochre pits. Red ochre pigments are well-known from various contexts on Rapa Nui, but until recently its origin and the extraction process involved in their production were not precisely understood. New excavations have revealed the presence of multiple pits used for pigment production and storage by the island’s prehistoric culture. Previous geoarchaeological studies, including geomorphological, pedological, geochemical and micromorphological analyses, have shown that the pits contain fine layers of reddish iron oxides (ochre), which result from repeated intentional burning. The oxide layers alternate with thin layers of phytoliths, interpreted as the remains of plant material used as fuel, and diatoms. This paper presents new phytolith and diatom data from the previously described site of Vaipú East, complemented with data from similar pits at the new sites of Vaipú West and Poike. New 14C dates are also presented from these sites. The phytolith and diatom data provide crucial information about the chaîne opératoire of the ochre production and the formation processes associated with the pits. The evidence of pigment production and storage at Vaipú East shows that labour-intensive ochre production took place on Rapa Nui during at least two separate phases after deforestation, while the pits discovered at other sites indicate that Vaipú East did not stand alone. This provides a further line of evidence in favour of cultural continuity rather than collapse following deforestation in the island’s late prehistory.