VLT/X-shooter spectrum (R = 7900) of J1019+1729 (black line) and the best fit derived by FERRE (red line). From top to bottom: the entire spectrum (3700–4400 Å). The range of the Ca ii lines. The H9 spectral region with several Fe i lines assuming T_eff = 5834 K, log g = 5.0 from our previous analysis over the entire spectra. The derived iron abundance is displayed. Finally the X-shooter spectrum smoothed to the OSIRIS resolution (R = 2500) and re-analyzed by FERRE: left panel shows the entire spectrum together with the derived metallicity while in the right panel a detail of the Ca ii lines is depicted.