Atomic% EDS dataset from acidic historic ink with precipitation, dissolution and translocation of jarosite

Chemical analysis on historic ink was performed through Energy-dispersive X-ray spectroscopy (EDS, INCA 250, Oxford Instruments). EDS microanalysis calibration used the following standards: CaCO3, SiO2, Albite, MgO, Al2O3, GaP, FeS2, wollastonite, MAD-10 feldspar, Ti and Fe (Agar Scientific Ltd, Essex, UK). A conventional ZAF correction (for Z atomic number, Absorption and Fluorescence) was applied to the EDS measurements. The microscope was operated at 10 kV for high vacuum SEM imaging and 20 kV during EDS analysis. Sixty-six single-point EDS analyses were used for the chemical characterisation of the observed objects (black ink, white/faded ink, yellow crystals, biological material).

Explanation of observations' names:

ink-W = faded ink;

jarosite = areas with blocky particles;

ink = black ink;

bio = areas with microbiological structures outside the ink.