Light Production by Ceramic Using Hunter-Gatherer-Fishers of the Circum-Baltic

Artificial illumination is a fundamental human need. Burning wood and other materials usually in hearths and fireplaces extended daylight hours, whilst the use of flammable substances in torches offered light on the move. It is increasingly understood that pottery played a role in light production. In this study, we focus on ceramic oval bowls, made and used primarily by hunter-gatherer-fishers of the circum-Baltic over a c. 2000 year period beginning in the mid-6th millennium cal BC. Oval bowls commonly occur alongside larger (cooking) vessels. Their function as ‘oil lamps’ for illumination has been proposed on many occasions but only limited direct evidence has been secured to test this functional association. This study presents the results of molecular and isotopic analysis of preserved organic residues obtained from 115 oval bowls from 25 archaeological sites representing a wide range of environmental settings. Our findings confirm that the oval bowls of the circum-Baltic were used primarily for burning fats and oils, predominantly for the purposes of illumination. The fats derive from the tissues of marine, freshwater, and terrestrial organisms. Bulk isotope data of charred surface deposits show a consistently different pattern of use when oval bowls are compared to other pottery vessels within the same assemblage. It is suggested that hunter-gatherer-fishers around the 55th parallel commonly deployed material culture for artificial light production but the evidence is restricted to times and places where more durable technologies were employed, including the circum-Baltic.