Ancient restoration practices in the Monumental Nymphaeum at Tripolis ad Maeandrum (Turkey): multi-analytical approach on Roman and Byzantine bonding mortars

The study of ancient architectural restoration has recently gained attention in the field of archaeometry thanks to a new sensitivity for the long biographies of human artifacts. The paper focuses on ancient repairs documented in the column shafts of the Monumental Nymphaeum of Tripolis ad Maeandrum (Denizli, Turkey). Bonding mortars used to hold the ancient patches in place were sampled and analysed according to a multi-analytical protocol, coupling mineralogical and petrographic investigation (XRPD and OM) together with FT-IR and chromatographic and mass spectrometric techniques (i.e. Py-GC-MS, GC-MS, HPLC-MS) for the characterisation of the inorganic and organic components. For the inorganic part, medium and fine-grained crystals of calcite are used as aggregates. As for the organic fractions, three different ingredients have been detected: egg, beeswax and Pinaceae resin. These multi-ingredient recipes detected in Tripolis are discussed with reference to ancient literary sources and the results of scientific investigations previously performed on ancient architectural repairs in the nearby city of Hierapolis of Phrygia, to highlight functional and chronological differences.