Could the grasses have played a role in the earliest salt exploitation? Phytoliths analysis of prehistoric salt spring from Hălăbutoaia - Ţolici (Romania)

International audienceThe salt spring exploitation from Hălăbutoaia-Ţolici (Neamț County, Romania) dates back to the Early Neolithic and lasted throughout Chalcolithic. The deposit stratigraphy is estimated at 8 m and covers 2500 years of history (c. 6000-3500 BCE). In order to document the possible use of plants, particularly of the grasses, in the salt production process, we realized a detailed study of phytoliths preserved in several archaeological levels of Hălăbutoaia site. The most identified morphotypes come from grass family. Analysis revealed an important representation of inflorescence bracts phytoliths (especially ELONGATE DENDRITIC) showing the anthropogenic origin of the assemblages. BILOBATE are also well represented. These forms attest the presence of wild panicoid grasses (e.g. wild millet) and/or cultivated millets in the area. In some very punctual assemblages, forms produced by dicots are well represented. Considering the low phytoliths production by dicots plants, it involves a special accumulation of these types of plants that could be related to woody plants used as fuel for salt production. It is very possible that grasses had a very important role in pyrotechnology used to produce salt, either as the main fuel or as a mean for controlling the temperature or even as a firelighter