This coin looks great, but it's hard to tell if it NT or AT. The actual colors make me feel AT, but I"ve seen similar colors, though not quite as vibrant on a morgan I own that I believe to be NT. It's funny with AT and NT, the only real difference most of the time is the process used, not the actual chemical reaction. The only real difference is whether induced naturally or artificially, but I feel good arguments can be that any toned coin is natural due to chemical processes. The fact it's only on one side make me feel NT, but the complete lack of toning on the obverse makes me feel AT. The randomness of the colors and pattens also make me feel AT, but you never know.