Both should be nickel. Now for the inspection and number stamps. The numbers should of the same size and from the same die style. As for the inspection marks. If you only have the "TO" (東) mark on them you will have the "TO" mark on the frame next to the date stamp ("A" position) and should not have the "N" stamp on the grip frame under the right grip. If you have the "N" mark only on the magazines you should find the "N" stamp under the right grip on the grip frame. If the mags have both marks than the pistol should have the the "TO" in the A position as well as the "N" mark under the right grip.