Bayesian modelling of an absolute chronology for Egypt's 18th Dynasty by astrophysical and radiocarbon methods

Only a few astrophysical points and synchronisms listed in texts provide anchor points for the absolute chronology of Ancient Egypt. At first we will show how we can re-calculate some of these anchor points by using Sothic dating based on the arcus visionis method, and modelling lunar dates using a Bayesian approach. Then, we will discuss two radiocarbon studies carried out on short-lived Egyptian materials held at the Louvre Museum that could be attributed to particular reigns or other precise periods. Using a Bayesian approach, these dates were combined with the known order of succession and the lengths of reigns. Sothic and lunar dates were integrated as priors in the model. This approach has led to a new proposal for the absolute chronology of Egypt's 18th Dynasty

Organic substances from Egyptian jars of the Early Dynastic period (3100–2700 BCE): Mode of preparation, alteration processes and botanical (re)assessment of “cedrium”

Organic substances from three jars found at Abydos in the tombs of Kings from the two first Egyptian dynasties (3100–2700 BCE) were investigated using gas chromatography–mass spectrometry in order to assess their biological origin, use and mode of preparation. The organic material was found to correspond to essential oils from conifers severely altered/oxidized. A predominant contribution from Cedrus libani was determined from the identification of sesquiterpenoid derivatives of the himachalene series which constitute new molecular tools for the identification of ancient oils made from real cedars. The presence of cuparene-related terpenoids suggests an additional contribution of members from the Cupressaceae family (junipers, cypresses). The genuine substances were most likely prepared in the Levant since neither C. libani nor junipers or cypresses are native from Egypt. Despite obvious analogies with “cedrium” used for embalming during later periods, their use as ingredients for embalming remains uncertain because true embalming only began in Egypt after 2500 BCE. Instead, it is proposed that these substances have been used as cosmetics, medicinal substances or for cultual purposes. The predominance of low molecular weight sesquiterpenoids and the absence of typical markers for wood tars indicate that the substances have possibly been prepared by steam-distillation of odoriferous plant material rather than by pyrolysis. Our study gives clues to the controversy concerning the composition of “cedrium”, indicating that it most likely originates from mixed true cedar and junipers or cypresses, and not exclusively from real cedar vs. juniper oil