7th Experimental Archaeology Conference Abstract – Christophe Snoeck
A Burning Question: Structural and Isotopic Studies of Cremated Bone in Archaeological Contexts
Research Laboratory for Archaeology and the History of Art, University of Oxford
Of the various burial practices used by humans, cremation is one of the most common; both nowadays and historically. Since 2001, cremated bone fragments are radiocarbon dated and much research has been carried out to try and understand why cremated bone provides reliable radiocarbon dates. Many bone fragments have been burned in controlled laboratory conditions but only few have been burned on outdoor pyres.
In order to study and understand cremated bone, it is crucial to burn bone in real environmental conditions. As part of my doctoral research, several outdoor cremations have been carried out using wood and coal. Different animal bones were burned, including lamb, pig, cow, and fish. The cremated fragments have been analysed by Fourier Transform Infrared Spectroscopy (FTIR) to observe structural and compositional changes. Some have been radiocarbon dated and carbon isotopic ratios (δ13C) have been measured by Mass Spectrometry (MS).
In the proposed paper, I present the first results of this research. Experiments show that very high temperatures (above 900ºC) can be achieved in outdoor conditions but that it is difficult to reach full calcination of bone: some parts will be white (calcined) while others will remain black (charred). Preliminary results indicate that bone structure changes drastically after cremation, and that bone exchanges large amounts of carbon with its surrounding environment during cremation: burned with coal, a modern lamb bone appeared to be 4,000 14C years old. The paper proposes some implications of these results on radiocarbon dating and bioarchaeology.