Radiocarbon Dating of Historical Parchments

Abstract

A range of pretreatment methods was applied to 6 known-age historical parchments to investigate the most suitable methods for effectively removing contamination and ensuring accurate radiocarbon dates while minimizing unnecessary destruction of potentially valuable historical documents. The methods tested included an acid wash, different concentrations of acid-base-acid (ABA) pretreatments, the current routine ABA method applied at the Oxford Radiocarbon Accelerator Unit (ORAU) that includes an additional bleach treatment, and extraction of collagen. The C:N atomic weight ratio of the untreated and pretreated parchment fractions was observed to be a useful indicator of the presence or successful removal of contaminants. The pretreatment methods that produced the most accurate 14C dates and acceptable C:N ratios were found to be ABA protocols (without bleach) and collagen extraction; solvent washes and acid pretreatments alone were not sufficient to remove all contaminants and produce reliable 14C dates. The inclusion of a base wash did not affect the 14C dates of the samples, but did favorably influence the C:N ratio of the final product.

Paging through history: parchment as a reservoir of ancient DNA for next generation sequencing

“…Thirdly, unlike bone remains, of which only a fractional percentage survives and much less have been excavated, all the skins are above ground, archived and in the case of legal documents, directly dated to specific calendar years and, usually, precise days, which is a level of resolution not readily achievable with any other historic DNA source. Even documents that do not carry a direct date can be dated palaeographically to a resolution better than radiocarbon dating (without the expense of this process) [ 5 ]. Finally, there is enormous interest in the genetics of the main parchment species, cattle, sheep and goat, each with vibrant research communities investigating both geographical and temporal genetic variation [ 6 – 8 ].…”

So you want to do biocodicology? A field guide to the biological analysis of parchment

“…Radiocarbon dating does provide a more precise form of dating, however this comes at a cost and is also generally reported as a calibrated date range. It necessarily requires destructive sampling of at least 3-10 mg [52] which, as we have previously discussed, is not routinely accepted by most conservators and curators and can therefore only be used when the object is considered of such high importance that the potential results merits the destructive samples [53][54][55][56]. We would also advocate that any sample remaining from a radiocarbon analysis be identified as the important biobank that it is and hopefully not discarded but used for other analyses.…”

Cross-Flow Nanofiltration of Contaminated Protein-Containing Material: State of the Art

“…14 C dating of leather textiles and parchments (a collagen-based writing medium made from processed, but untanned, skins of cattle, sheep, and goats) are also increasingly conducted (Mannering et al 2010; Brock 2013). Until recent times, dating of textiles was based on stylistical methods but 14 C dating can refine and/or improve this stylistical dating (Van Strydonck et al 2004; Mannering et al 2010).…”

“…Until recent times, dating of textiles was based on stylistical methods but 14 C dating can refine and/or improve this stylistical dating (Van Strydonck et al 2004; Mannering et al 2010). The importance of 14 C dating of parchments is that parchments provide a lot of archaeological and historical information, both from the written information on the parchment and also relating to the processes involved in the manufacture (Brock 2013). Quality control of parchments can be done by analyzing the C:N ratio and comparing them with the C:N range of collagen defined by De Niro (1985) as they are untanned (Brock 2013).…”

“…The importance of 14 C dating of parchments is that parchments provide a lot of archaeological and historical information, both from the written information on the parchment and also relating to the processes involved in the manufacture (Brock 2013). Quality control of parchments can be done by analyzing the C:N ratio and comparing them with the C:N range of collagen defined by De Niro (1985) as they are untanned (Brock 2013). However, setting up a quality-control parameter for tanned leathers is more challenging because tanning will increase the C:N ratio due to the chemical composition of tannins.…”