We present the analysis of an osseous finger ring from a predominantly early Neolithic context in Denmark. To characterise the artefact and identify the raw material used for its manufacture, we performed micro-computed tomography (Micro CT) scanning, zooarchaeology by mass spectrometry (ZooMS) peptide mass fingerprinting, as well as protein sequencing by liquid chromatography tandem mass spectrometry (LC-MS/MS). We conclude that the ring was made from long bone or antler due to the presence of osteons (Haversian canals). Subsequent ZooMS analysis of collagen I and II indicated that it was made from Alces alces or Cervus elaphus material. We then used LC-MS/MS analysis to refine our species identification, confirming that the ring was made from Cervus elaphus, and to examine the rest of the proteome. This study demonstrates the potential of ancient proteomics for species identification of prehistoric artefacts made from osseous material.

Micro CT was used to examine the ring using the commercial Zeiss Xradia410 versa system. The ring was rotated 360 degrees in 1601 steps taking a picture at each step using a pre-voltage of 80kV and a power of 10W. Two measurements with different pixel resolutions were performed at 32.3 and 13.5 µm. The 3D volume was reconstructed using the software provided with the instrument system “Reconstructor”, which is based on a Feldkamp-Davis-Kress algorithm (Feldkamp, Davis and Kress 1984). The resulting 3D volumes are cylinders with a diameter and height of 3.2 cm and 1.35 cm respectively corresponding to the different pixel resolutions, containing different amounts of the object. Visualisation was performed using ‘Avizo 9.7’ (Thermo Fisher Scientific). The volume investigated with high resolution X-ray micro CT, has been segmented into elements of the bone (shown in transparent gray) and porosity in the bone (shown in blue). The different levels of blue are a result of the amount of transparency.