The veneer strips were measured using the laboratory 6500 system fit with a coarse sample cell (which has a window size of 185 mm · 35 mm). The strips were mounted in the cell with the tight-side facing towards the detector. Subsequently the cell was attached to the sample transport system, which moves the sample along the beam/ detector area while scans are recorded, thus yielding an average spectrum across the whole length of the sample. Spectra were acquired in reflectance mode using 32 sample scans and 16 background scans (against an internal ce- ramic standard).