Casting technology of Renaissance bronze statuettes: the use of TOF-neutron diffraction for studying afterwork of Renaissance casting techniques

Abstract

The finishing techniques of Renaissance bronze statuettes of the Rijksmuseum Amsterdam were examined using Time of Flight Neutron Diffraction (TOF Neutron Diffraction) at the Rutherford Appleton Laboratory in Chilton on the diffractometer ENGIN-X. The research focused on the hypothesis that a bronze sculpture from the Renaissance that seems meticulously finished could have been cast without any afterworking of the surface using chasing tools. The statuettes with this specific feature are Willem van Tetrode's Hercules Pomarius (BK-1954-43) and Bust of Pope Gregory XIV manufactured by Bastiano Torrigiani (BK-16937). Both of these sculptures date to the second half of the 16^th century. A study of contemporary treatises indicated that casting without chasing was possible. For comparative results a bronze figure from the beginning of the 16^th century, doubtlessly cast and chased, representing Paris by Severo da Ravenna (BK-1959-4), was equally analyzed. Reference samples reproducing the techniques involved were manufactured to compare the results with the original objects. We could prove that both the Bust of Pope Gregory XIV and Hercules Pomarius were cast and not chased and Paris was cast and chased.