Reflections into Ptolemaic glass: Colorless, white, blue, and green inlays from the workshop of Tebtynis

Inlays range among the most aesthetically pleasing and technically challenging glasses produced in the Ptolemaic period. Despite the central role of this phase in the history of glass technology, little is known about the recipes and the technological knowledge of the Egyptian artisans. This paper will thus focus on the study of the materials from the secondary workshop of Tebtynis (Fayum oasis, Egypt). We report the first multi-methodological study comprising textural, chemical, and mineralogical analyses (optical microscopy, scanning electron microscopy coupled with energy-dispersive system, electron probe microanalysis, and mu-Raman spectroscopy) on a set of 81 colorless, white, blue, and green samples carefully selected among the 800+ glasses from the craft area now stored at the Museo Egizio, Turin (Italy). Our study offers the biggest compositional database of well-dated Ptolemaic glasses currently available in the literature, highlighting some interesting novelties regarding the silica and alkali sources, and the coloring and opacifying techniques employed. The results suggest a specialized craft of traditional origin, but open to innovation and experimentation, as expected from transitional phases.