Laser-induced Breakdown Spectrocopy (LIBS) analyses of glass without grisaille (body surface) and the grisaille itself were performed using laser excitation at 266 nm (Nd:YAG laser, 6 ns pulses, 10 Hz repetition rate; Quantel Brilliant) and a 0.30 m spectrograph with a 1200 grooves/mm grating (TMc300 Bentham) coupled to an intensified charged coupled detector (ICCD, 2151 Andor Technologies). The fluence was of 6.6 J cm− 2. LIBS spectra were recorded with a gate delay and width of 100 ns and 3 μs, respectively. For the Laser-induced Fluorescence (LIF) analyses, the same equipment described above was used. However, time gate was operated with a zero-time delay, the grating was 300 lines/mm and the number of accumulations of 25. The fluence was 6 × 10− 3 J cm− 2. A home-made nonlinear optical microscope (NLOM) was used for Multi-Photon Excitation Fluorescence (MPEF) measurements of grisaille thickness with a mode-locked Ti:Sapphire femtosecond laser. The laser emits at 800 nm, with an average power of 680 mW, delivering 70 fs pulses at a repetition rate of 80 MHz and a laser power of 6–9 mW. The laser beam was modulated using a chopper at a frequency of 130 Hz and conducted to the sample through the aperture of a microscope objective lens (M Plan Apo HL 50X, Mitutoyo, NA 0.42). The focal plane of the laser was selected with motorized translation XYZ stages (Standa 8MVT100-25-1 for XY and Standa 8MTF for Z). In-depth cross section imaging of carbon coated glasses decorated with grisaille paint was carried out by Field Emission Scanning Electron Microscope (FESEM) with a Hitachi S-4800 cold cathode equipment, working with acceleration voltage of 15 kV. An Oxford X-Max of 20 mm2 system coupled to the electron microscope with resolution of 125 eV (Mg Kα) was used for Energy Dispersive X-Ray Spectroscopy (EDS) microanalyses. More details of the experimental conditions are available in their respective data folder. Data life: 2021- (unlimited validity). This dataset is subject to a Creative Commons Attribution 4.0 International (CC BY 4.0) License.

This is the experimental dataset used in the paper Talanta, 230: 122314 (2021) (http://hdl.handle.net/10261/244443) in which the thickness and composition of grisaille paints in four Spanish historical stained glasses, named Balmaseda (A; 19th century), Girona (B; 18th century), Leon (C; 13th century) and Goyeneche (D; early 20th century) after their place of origin, have been determined. The samples are glass fragments without value for their replacement available from previous conservation works made by some of the authors. This data set includes the results of the chemical and physical characterization of grisaille with a set of optical and spectroscopic techniques, including non-invasive techniques such as the emerging Nonlinear Optical Microscopy (NLOM) in the modality of Multi-Photon Excitation Fluorescence (MPEF). This allows determining the thicknesses values of the historical grisaille paint layers on the basis of their intrinsic fluorescence without photochemical and physical damage. The results obtained (FWHM values of depth scan after refractive index correction) show significant consistency and agreement with those obtained from traditional Field Emission Scanning Electron Microscope (FESEM) in which mean thickness varies between 26-78 µm. Scanning Electron Microscope coupled with Energy Dispersive X-Ray Spectroscopy (FESEM-EDS) and Laser Induced Breakdown Spectrosocopy (LIBS) show the elemental composition of both the body glass and the grisaille paint in the 4 samples according to the respective emission lines of the main and minor components. And finally, Laser Induced Fluorescence (LIF) provides complementary information (fluorescence species).

dc.description.tableofcontentsLIBS folder: LIBS_readme; LIBS_A-glass; LIBS_A-grisaille; LIBS_B-glass; LIBS_ B-grisaille; LIBS_C-glass; LIBS_C-grisaille; LIBS_D-glass; LIBS_D_grisailleLIF folder: LIF_readme; LIF_A-glass; LIF_A-grisaille; LIF_B-glass; LIF_B-grisaille; LIF_C-glass; LIF_C-grisaille; LIF_D-glass; LIF_D-grisailleNLOM folder: NLOM_readme; NLOM_A-grisaille_l; NLOM_A-grisaille_h; NLOM_B-grisaille_l; NLOM_B-grisaille_h; NLOM_C-grisaille_l; NLOM_C-grisaille_h; NLOM_D-grisaille_l; NLOM_D-grisaille_hFESEM-EDS folder: FESEM-EDS_readme; EDS_A-grisaille; EDS_B-grisaille; EDS_C-grisaille; EDS_D-grisaille; FESEM_A-grisaille; FESEM_B-grisaille; FESEM_C-grisaille; FESEM_D-grisaillePHOTOS folder: Photos_redame; A-glass_grisaille; B-glass_grisaille; C-glass_grisaille; D-glass_grisaille O

We acknowledge financial support from the Spanish State Research Agency (AEI) through projects PID2019-104124RB-I00/AEI/10.13039/501100011033 and PID2019-104220RB-I00/AEI/10.13039/501100011033; from the Community of Madrid through project TOP Heritage-CM (S2018/NMT-4372); from European Union’s Horizon 2020 through IPERION HS (Integrated Platform for the European Research Infrastructure ON Heritage Science, GA 871034) project and CSIC through M.O.’s contract.

Peer reviewed