vintage Navajo(?) ring, signed RD

i’ve never seen anything quite like this ring. fine silver work and a stone which i assume is a CZ. marked RD and sterling. thoughts?

![IMG_9453|465x500]

Hello, we see rings with a cz frequently and done and all different designs. Hougart’s has a Robert Dalton, Ray Delgarito, Reginald Dewakuku and a Rose Castillo Draper associated with an RD hallmark, you might do a google search with each name to see if you find a similar style.