Reflections into Ptolemaic Glass II: Characterizing Yellow, Yellowish-orange, Red, and Brown Inlays from Tebtynis

A systematic and extensive analytical study was carried out on the loose inlays discovered in the Ptolemaic workshop of Tebtynis (Fayum oasis, Egypt). This paper presents data derived from the multi-methodological archaeometric investigations (optical microscopy, scanning electron microscopy–energy-dispersive spectroscopy, electron probe microanalysis, micro-Raman spectroscopy) performed on a set of intentionally colored and opacified glasses. In particular, we will discuss the textural, chemical, and mineralogical results related to the study of the yellow, yellowish-orange, red, and brown inlays and semi-finished/waste products now preserved at the Museo Egizio, Torino. The results highlight the presence of natron (low-magnesium glasses, LMG) and plant ash (high-magnesium glasses, HMG) base glass, coexisting with intermediate composition. Yellow samples are opacified using lead antimonates doped with iron and sometimes tin; conversely, yellowish-orange specimens and the only brown sample are characterized by nanocrystals of cuprite. Red glasses are found in two variants: Dull reds are HMG with colloidal metallic copper particles, while sealing-wax reds show LMG composition, associated with dendritic cuprite dispersed in a transparent, greenish matrix.