Mapping of cracks, defects, and cast-on metal on the heavily repaired right ankle of the Perseus monument was undertaken, before restoration, using an Eddy current probe (red and white lines) and a microwave probe (yellow lines and dots). Eddy currents detect all areas of discontinuity in a metallic surface. White lines are the outline of the cast-on repair, which was difficult to see and includes adjacent circular plugs that help lock the patch to the metallic wall. Microwaves detect air bubbles (yellow dots) or areas of discontinuity even under the surface. The round area at top right represents a sprue and was visible under raking light. Benvenuto Cellini (Italian, 1500–1571), Perseus with the Head of Medusa, 1545–54, H. 320 cm (bronze group); 199 cm (base, modern) (Loggia dei Lanzi, Piazza della Signoria, Florence). Morigi Restauratori, unpublished conservation report.