This is a gorgeous silver Navajo vintage pony pin or brooch with a small turquoise stone as his eye.  He is so handsome and jaunty.  He is unmarked (or very lightly marked), but I believe him to be a United Indian Traders Association (“UITA”) piece as I had one almost identical which was clearly stamped.  This organization was established in the early 1930s so tourists would know they were buying a true American Indian product.  He measures close to 3″ across and about 2 1/4″ down.  He is a nice size and showy on your jacket or blouse.