Functional exploration of grinding and polishing stones from the Neolithic settlement site of Oldenburg LA77, Northern Germany − evidence from plant microfossil analysis

• This research is the first exploration of the possible function of grinding and polishing stones from a Neolithic FBC (3270–2920 BCE) settlement site in northern Germany through plant microfossil analysis. • The plant microfossils recovered from this study are informative on the processing of various organic substances, including the cereal grains of Triticeae; fruits of Poaceae p.p. and Avena sp.; nutlets of Polygonaceae and Cyperaceae; nuts of Quercus sp.; starch-rich USOs; and, possibly, a small number of seeds of wild legumes. These grinding stones are therefore best defined as multi-functional tools. The same holds for the function of polishing stones, which challenges the notion that polishing stones were used as tool sharpeners only. • The results produced by this study also added new insights into the controversial ethnological observations on the relationship between the use and the physical features of grinding stones. After plotting the three physical features of grinding stones, their morphology, raw material, and size, against their functions as determined through micro-botanical analyses, we conclude that food processing stones with different physical features tend to be used in an identical method. • This study also identified the possible social/ritual function of grinding stones at Oldenburg LA 77. We see no significant functional differences among grinding stones linked with economic and ritual activities; therefore, in addition to being used as part of economic practices both domestically and collectively, after being freshly broken, grinding stones were chosen to be deposited by local inhabitants to participate in the ritual activity. • The answers to the questions we raised in this study feed into major discussions on a more social scale that relate to the establishment of the first village communities of Funnel Beaker groups. The results indicate that grinding and polishing stones were used to process a wide range of cereals and other plant resources, and more importantly, grinding stones may have been chosen as part of ritual activities and perhaps imbued with ideological meaning. Analyses of plant microfossils retrieved from grinding and polishing stones are shown to constitute a reliable line of evidence to unveil the functions of these stone implements at the site of Oldenburg LA 77. Dating to the Middle Neolithic (3270–2920 BCE), this settlement is one of the earliest villages that are representative of the social shift in northern Germany, from living in isolated farmsteads in the Early Neolithic towards population agglomeration in villages in the Middle Neolithic. Our results paint a complex picture of the use of grinding and polishing stones in daily plant preparation: they were predominantly used to crush and/or grind cereals, but also regularly used to grind wild grass caryopses, tubers, rhizomes, and, to a lesser extent, wild legumes. We see no significant functional differences among the sampled grinding stone tools linked with different stone morphotypes, stone raw materials, as well as stone sizes. Our results also indicate that daily food processing-related grinding stones may have been deliberately chosen, invested with social meaning, eventually became part of ritual activities in the settlement, and thus, may have additional functions beyond economic practices.