Interpreting the age of the ruins of St. John the Baptist's church with multivariate analysis

Two multivariate statistical tools - principal components analysis and cluster analysis - were applied to aid in the interpretation of the historical development of St. John the Baptist's church (Žiče, Slovenia). With these methods it was possible to distinguish between the types of mortar used in the Romanesque and Gothic time periods. The investigated structure is a ruin with poorly preserved fragments of historical mortars, so tracing the individual stages of its construction proved to be a demanding task. Its chemical composition was determined by inductively coupled plasma mass spectrometry (ICP-MS) and the results of the content of various oxides were statistically evaluated to interpret the age of the southern wall of the church.