In the present study, a historical set of Late Roman glasses coming from a recently unearthed graveyard located in the small city of Cubas de la Sagra, within the Madrid region (Spain) was compositionally analysed using different techniques such as ultraviolet-visible (UV-Vis) and laser induced fluorescence (LIF) spectroscopies, X-ray fluorescence (XRF) and laser induced breakdown spectroscopy (LIBS). LIBS results, recorded upon nanosecond (ns) and femtosecond (fs) laser irradiation, served for identification of major glass components (to classify them into main historical glass groups) and of minor components (e.g. chromophores, decolouring agents and degradation products). Quantitative information regarding these components was obtained on the basis of calibration curves obtained using glass certified standards and local standards. We have demonstrated that LIBS serves for the noninvasive/micro-destructive, quantitative chemical characterization of most of the analysed historical glasses. Furthermore, this work establishes a comparison between LIBS analysis of glasses in the ns and fs regimes on one hand, and on the other hand with the results obtained 2 using XRF. The procedures and protocols here proposed can be applied for in-situ study of historical glass collections, regardless of their size, provenance and chronology.

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This paper reports the analyses of infrared thermography images of two stained‐glass windows with the objective of the in situ characterization of this type of artworks. The analyses were carried out by active thermography. The observations revealed that glasses absorbed the long‐wave IR radiation emitted by the halogen lamps and their apparent surface temperature progressively increased. After switching the spotlight off, they experienced a progressive decrease in temperature. Silver stained glasses presented the same thermographic behavior than uncolored glasses because silver nanoparticles were too small or the yellow layer was too thin to produce a different response than the base glass with the IR radiation. The apparent surface temperature of enamels and grisailles depended on their thickness and color. Lead cames maintained an almost constant surface apparent temperature, except those painted that behave in a similar way than enamels. Metallic tin‐lead welds experienced the most important variation in the surface apparent temperature in reflection mode due to the energy reflected by the surface of the weld. Glass defects such as big bubbles were also observed.

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