Gaming pieces made from the first phalanges of cattle are relatively common finds in the medieval and post-medieval archaeological record in Northern Europe. A total of 32 worked cattle first phalanges have been recovered from the town of Turku, Finland, in archaeological excavations so far. In this article, we present a new study and interpretation of all known modified cattle first phalanges from the Turku excavation material as well as a comparison with the available ethnographic material. Modified cattle phalanges were recovered from seven archaeological sites across medieval Turku and from areas of various social standing. The results show variability in the modification of the cattle phalanges. Bones could be filled with e.g. wood, lead or an iron nail. Consistencies of metal fills were examined with a pXRF. In this study, X-radiography proved to be an effective method to examine these bones as all details are not visible otherwise. For example, in one bone there is a metal alloy object hidden inside, visible only in X-ray.