Comparison of meteorite spectra in the 540–550 nm range demonstrating the variable strength of the Ni I-59 line. Upper panel: differences between the high-resolution Echelle spectra of three meteorites. The lines marked by X are artifacts of the Echelle reduction. Lower panel: AMOS spectra of three different meteorites illustrating the possible identification of the Ni I in lower-resolution data. The Ni I line was detected in the iron and stony-iron meteorites, and in all chondrites, while it is absent in all tested achondrites (also see Fig. 10). In both images, the spectra are normalized to unity at 526.95 nm (peak of the strongest Fe I-15 line).