Application of different protocols and age-models in OSL dating of earthen mortars

Abstract

Abstract:In this study, OSL dating was applied to earthen mortars, consisting in a quartz-rich aggregate dispersed in silty-clayey matrix. The samples were taken from two independently dated structures in Cremona, Northern Italy (Palazzo Raimondi, 1495-1499 AD and Palazzo Soldi, 1770-1790 AD). The evaluation of the equivalent dose (D e ) was attempted with both the multigrain and the single grain protocols using the 150-250 μm quartz fraction. The reliability and effectiveness of the various statistical methods in identifying the well-bleached samples were tested. The use of the multi-grain technique gave unreliable results, due to the high amount of poorly bleached grains. With the single-grain technique, more promising results were obtained: in particular, the un-log MAM3 and IEU models allowed an accurate evaluation of the mortar expected age in most cases, even if the precision is still relatively low.

Luminescence and Radiocarbon Dating of Mortars at Milano-Bicocca Laboratories

“…The further application of the MAM statistical method could greatly improve the accuracy of the experimental data. However, neither its application nor that of other statistical methods developed to obtain the best selection of the fully bleached grains (the internal-external consistency criterion, IEU, Thomsen et al 2007 or that recently proposed by Guibert et al 2017) could guarantee successful dating in a few of our previous case studies (Panzeri et al 2017).…”

“…As OSL mortar dating is not yet an accepted dating technique, we tried to validate it on samples from independently dated sites (Panzeri 2013;Panzeri et al 2017Panzeri et al , 2019Tirelli et al 2020). In total we analyzed 22 samples, using both multi-grain (MG, Fleming 1970) and single grain (SG, Murray and Roberts 1997;Bøtter-Jensen and Murray 2002) techniques, which did not always give satisfactory results.…”

The State-of-the-Art of Dating Techniques Applied to Ancient Mortars and Binders: A Review

“…"Single Grain" OSL Dating of Historical Monuments After the first series of exploratory papers applying mainly a classical "multigrain" procedure and discussed at the beginning of this paper, larger "single grain" OSL dating studies were performed on mud mortars (Feathers et al 2008; 16 prehistoric samples), on lime mortars (Urbanová and Guibert 2017; 33 samples with the known historical age) and on earthen mortars (Panzeri et al 2017; 10 samples with the known historical age). Feathers et al (2008) presented the first larger "single grain" OSL dating study on mortars which was integrated in an archaeological research project on the prehistoric site Chavín De Huántar in Peru.…”

“…Finally, Panzeri et al (2017) reports the SG-OSL dating of 10 earthen mortars from two 15th and 18th century monuments in the Cremona, north-central Italy. The IEU and the unlogged-MAM model were stated as the most appropriate for the calculation of the archaeological dose for the given set of samples.…”

“…"Single Grain" OSL Dating Potential of Mortar and Provenance of Quartz? Based on the SG-OSL studies of European historical mortars published up to now, we have an insight on four late medieval sites from central-north Italy (Panzeri 2013;Panzeri et al 2017Panzeri et al , 2019, three medieval sites from Switzerland (Urbanová and Guibert 2017) and many examples of early medieval architecture from southern France (Urbanová and Guibert 2017;Urbanová et al 2018;Javel et al 2019), northern Croatia (Čausević-Bully et al 2018), northern Italy (Panzeri et al 2017;Urbanová 2019) and southern Spain (Urbanová 2019). Apart from a study of one pre-Columbian site from Peru (Feathers et al 2008), other research on the SG-OSL dating of mortars outside Europe is lacking.…”