What in the world is it? My only guess is to clasp a thick scarf at the shoulder. Scottish? Any information is welcome! It is well made with rivets holding green stones and interior spring to adjust to thickness, I presume. Good, solid clasp too. Measures 2 1/4 inches and golden finish shows no wear. Excellent mysterious vintage. I have a similar one with purple, pink and blue stones. It could be a 2-for at $25.