What’s This? Early 20th Century Doo Dad

This early 20th century mystery glass ornament comes from my friend Jessica’s grandmother. It is very pretty, with a fancy satin glass cab done up in an intricate weave pattern. I just wish I knew what it was for. May the top part of an ornate hat pin? A strange sash or belt buckle? If you have any guesses, please let me know in the comments. It’s drivin’ me crazy!