Lipid markers in archaeological pottery vessels excavated at Jneneh Site, in North-Central Jordan

This study is part of a long-term project attempts to better understand the content and use of pottery vessels in the Bronze and Iron Ages in Jordan by examining organic residues preserved in their interior fabrics. The main purpose of this study is to analyse organic residues retained in a second collection of Iron Age II pottery sherds excavated at the site of Jneneh in North-Central Jordan, in order to determine the content and the potential use of the mother vessels based on integrating data obtained from this bimolecular study with those found in the archaeological record. The analysis was applied on these sherds and their associated soils. Residues were retrieved from the pottery fabrics and soils using the conventional solvent extraction method. One portion of each residue was analysed using gas chromatography-mass spectrometry (GC–MS) technique, and when needed, another portion was first saponified (alkaline hydrolysed) and then analysed. The analysis revealed the existence of: (1) Markers related to two materials preserved in a sherd that belongs to a coarse storage jar with collared decoration (Jn9; Class 1). The first material is beeswax, which may have intentionally been applied as a sealant on the inner side of the jar in order to store aqueous liquids like water or to store dry goods. Using the jar for storing honey, which probably was not completely filtered from beeswax, was also proposed. The second material is being of plant origin, possibly oil or mixture of oils, preserved as a result of using the same jar for storing, either before or unlikely after sealing the jar with beeswax. Using both materials as a mixture inside the jar was also suggested. These two materials reoccurred for the second time in vessels from the same site. (2) Markers related to animal fat (possibly ruminant-based milk lipid, which requires confirmation) preserved in a sherd that belongs to a fine miniature jug (Jn4; Class 2), which was probably used for holding the milk products for daily based use. (3) Markers with very low concentrations related to a plant wax originated from unknown source were also observed in seven pottery sherds (Class 3), some of these sherds have contamination signals from handling and modern materials. (4) Few number of undiagnostic markers with very low concentrations were also detected in other five sherds (Class 4), therefore, their origin could not be determined. The organic contents of the latter two classes, and particularly Class 4, may have been subjected to a high level of degradation and depletion, therefore, residue analysis of this study could not provide data on the use of Classes 3 and 4 mother vessels but archaeologically their potential uses were discussed in this paper. Analysis of the markers present in the soils adhering onto the surfaces of pottery sherds provided evidences on the occurrence of lipid-based natural materials inside Jn9 and Jn4 vessels and on degradation and depletion of organic contents, as well as contamination from soil lipids in case of the other vessels. Hence, this study presents further evidence on, possibly, the common use of bees and plant products in the IA II settlement at Jneneh.