Fig. 3

NEXAFS spectra extracted from the regions of interest of the unsized and inked fiber I (a), sized and inked fiber G_I (b) and gelatin sprayed inked fiber I_G (c). The spectra correspond to the Fe L-edge (left) and C K-edge (right). They were extracted from the stacks in the region of interest 1–10 represented in Figs. 2, 4, 5. C K-edge spectra were normalised with the Athena software. Fe L-edge spectra are presented un-normalized to better assess the relative amount of iron present in the thin section