Variability and complexity in calcite-based plaster production: A case study from a Pre-Pottery Neolithic B infant burial at Tel Roʻim West and its implications to mortuary practices in the Southern Levant

The production of lime plaster is considered as one of the hallmarks of the Pre-Pottery Neolithic B [PPNB] period in the Southern Levant, where lime plaster has been used not only in architectural but also in mortuary contexts. In this study we investigate the technology used to produce plaster associated with an infant burial found in the PPNB layers at the site of Tel Roʻim West [TRW]. Bulk sediment samples and undisturbed impregnated sediment block samples were studied using Fourier Transform Infrared (FTIR) spectroscopy, micromorphology and micro-FTIR. In addition, we report the results of experimental heating of chalk and marl used as geological reference materials. The results indicate that plaster associated with the burial appears in various compositions, and that none of them is based on pyrogenic production of lime. Rather, these plaster materials are composed of calcite-based crushed/ground local marl and/or chalk that were mixed with anthropogenic remains including fired-clay aggregates, burnt (carbonised) chalk fragments, bones and vegetal matter (the latter clearly used as temper). The case study from TRW provides new insights regarding the production of non-pyrogenic calcite-based plasters in mortuary contexts during the PPNB. This study calls for a re-consideration of archaeological plaster technology: while in the field it is often assumed that PPNB plaster is a product of pyrotechnology our results suggest that in certain cases archaeologists should consider other, non-pyrogenic, technologies of plaster production. We argue for a more widespread use of non-pyrogenic calcite-based plaster than previously suggested, not only in architectural but also in mortuary contexts. We discuss the social, ecological and technological roles plaster production played in PPNB societies in the Southern Levant.