The art of imaging methods—using cutting edge radiological technology to uncover the secrets of ancient anatomical figurines

Ivory anatomical figurines are thought to have been carved in Germany in the seventeenth or eighteenth century. While it is speculated that these figurines were used for the study of medical education, little is known about their origins. A precise understanding of the composition of these figurines may further provide knowledge about their purpose and exact age. Our institution holds the largest North American collection of these figurines. Our purpose was to utilize micro-computer tomography (micro-CT) to determine the composition of these figurines and discern whether these figurines are made of “true” ivory (e.g., elephant or mammoth tusk) or other ivory-like materials (e.g., whale bone and antler). Scans of 22 figurines were performed on an XT H 225 ST Nikon Micro-CT (mCT) scanner at 150–200 kV, with an average exposure time of 267 ms, and slice thickness of 40–80 μm. Axial micro-CT slices were evaluated for Haversian canal structure/morphology to determine material composition. micro-CT images were also evaluated for materials other than ivory or bone that were not appreciable by visual inspection. Out of 22 figurines, 20 were made of ivory, one was made of antler, and one contained both ivory and whale bone. Metallic components and/or fibers were found in a minority of figurines. Twelve figurines contained hinges or internal repairs. micro-CT can be used to discern the composition of fragile archeological figurines and assess for repairs or alterations. This information may enable archeologists to draw conclusions regarding objects’ age, origins, and possible uses.