Vintage 12K Gold Filled Filigree Bar Rope Chain Bracelet with Center Diamond

Vintage 12K gold filled, filigree bar bracelet with a small center diamond stone and rope chain. Spring clasp closure is marked 1/20 12K GF. The bar is marked 12K GF. The bracelet measures about 7 inches long. The bar is pliable and is bent down on each end and some waves on one side. I do not know if some of it is by design or use. I tested the stone and it verified it has a diamond. It is a very small stone. There is a hallmark on the underside of the bar which looks like CR to me but I have not been able to identify the maker. The clasp is also marked gold filled. Lovely art deco style bracelet. In good pre-owned, vintage condition with some signs of wear from normal use.