The preservation of cultural heritage artifacts in seismic regions is increasingly important due to their vulnerability during earthquakes. While much attention has been devoted to historic structures, museum contents such as statues remain less protected. To address this gap, a novel bi-directional base isolation system using the patented Kinematic Steel Joint (KSJ) has been developed. The KSJ features a double articulated steel quadrilateral with crossing rods, providing self-centering, energy dissipation, and pendulum-like behavior in a compact and cost-effective design. An extensive experimental campaign was carried out at the L.E.D.A. Research Institute of Kore University of Enna. The testing included quasi-static trials for geometric assessment, broadband noise excitation for evaluating dynamic transmissibility, and shake table simulations based on real earthquake records to assess system performance in terms of transmitted accelerations and displacements. A full-scale replica of the Statue of the Goddess of Morgantina was mounted on the KSJ device to assess its protective efficiency under seismic loading. The isolator effectiveness in reducing seismic accelerations transmitted to the statue had already been demonstrated in previous studies by the same authors. In this study, an analytical model of the coupled KSJ–statue system is developed, calibrated and validated against experimental data, providing an accurate numerical representation of its dynamic response.