The early Neolithic site of La Marmotta is located on the shore of a lake of volcanic origin on the present-day Lake Bracciano in the Lazio region, central Italy. The settlement presents an extraordinary preservation of organic material by water-logging, with radiocarbon dates in the early 6th millennium BC. La Marmotta has provided remarkable and diverse basketry and ceramic material, such as decorated pottery vessels, and stone implements including complete well-preserved sickles, in addition to a wide range of macrolithic stone tools, including grinding stones. The current study enlarges functional and phytolith evidence from grinding tools, building up on previous technological and use-wear studies as well as on comparative experimental records, in an effort to gain a better understanding of tool-use and plant processing. Pilot technological and use-wear studies suggested that grinding stones were probably involved at different stages of plant processing, including cereal grinding and dehusking. Phytoliths further indicated the nature of the vegetal processed matter, including cereals such as wheat and barley. The size of multicellular phytoliths from tool active surfaces also pointed to dehusking and grinding activity, according to experimental cereal processing datasets, including hulled barley and einkorn wheat, which dominate the macrobotanical records at the site, along with emmer and free-threshing wheat. These results further point towards the value of functional and microfossil evidence for tracing plant processing activity and the fundamental role of grinding tools in early built environments.
