I have exhausted the search for this hallmark, couldn’t find anything. I keep waning it to be an N with a T,J, something besides just an N. I worked through the names with just an N hallmark and the only one that had chip inlay attributed to his name was Stanley Curley. However, when you look up his hallmark it has a crescent and the N looks different. It doesn’t mean he could have used another hallmark over his career. You bracelet is Navajo and it is chip inlay.
The other piece I don’t believe to be Navajo, Zuni or Hopi made. It could be Native but not the style you find here in the Southwest.