Genuine Gemstone Pin Garnets Sapphires Fine Vintage Jewelry

GORGEOUS! I was told that the stones are genuine garnets and sapphires. Not sure what the clear stones are. Perhaps white sapphires? The pin is quite large and measures 2 1/2" long. All stones are open backed. I find no maker's marks anywhere. It tested positive for 10k gold, but I think this is either gold plate or possibly gold filled. I don't think it is 10k gold.

There is a dark mark on the back of the stem at the end and the end of the pin shaft has some wear. Regardless, it is a show stopper!