Twenty-six objects from the Delphi archaeological Museum, including nearby museum premises, have been analysed by portable XRF. The aim was their characterization, provenance and archaeological interpretations. Twenty-one miniature Corinthian ceramic vases, a bronze and a ceramic pyxis bearing powder, four pigments on ceramics and six elegant glass vases, were non-destructively measured in situ. The ceramic analysis seems to form one cluster with similar chemical traits. The clay is calcareous with relatively high iron and titanium contents. Slip painted surface was due to increased MgO and Fe2O3. Four elegant glass vases were statistically compared to about 270 published data of similar period for provenance study and investigating the mineral agents for colouring glass. In fact the clustering analysis forms one of the major analytical groups containing the Delphi samples and also samples from Rhodes and Satricum. Of the major findings is the highly toxic mercury as cinnabar (HgS), a red pigment very commonly used since antiquity, mixed with PbO white lead in face powders. Particular elemental variations in all groups are discussed. Multiple statistical analysis was used, such as, various hierarchical cluster versions, PCA, bi-plots. The case study provides a practical aid to archaeological interpretation and emphasizes the valuable use of portable XRF in museum studies on material culture ranging from various types and periods.