1930s Navajo Thunderbird Concho Belt Converted to Necklace!

Early 1930s Navajo solid sterling silver rectangular concho belt piece that was converted to a necklace. It is 23 1/2" long and is missing it's buckle. (People had much smaller waists in the 1930s.) It has a lobster claw clasp that is modern and not sterling. Conchos measure 1 1/2" by almost 7/8" wide. Great hand stamping with Thunderbird in the center of each concho. This particular stamp is one that I have never seen before. Weight: 81.6 grams. No hallmarks. Acid tested. Good early one with a warm patina. Found in Arizona.