For the study of the NAM’s stone artefacts, the laboratory, utilizing the museum’s logistical infrastructure, introduced a diagnostic protocol of detection, analysis and documentation. In the context of this protocol, various photographic techniques (VIS, RTI, UVF, UVR, VIL, IR) are applied to investigate the colour residues in ancient works and previous interventions on them as well as X-RAY, γ-RAY, mainly to investigate the internal assemblage of reconstructed sculptures. In addition, the analytical method of x-ray fluorescence (XRF), with non-invasive organology, is used to determine the chemical elements (qualitative-quantitative elemental analysis) of which the various inorganic materials and matter found in the artefacts are composed.