A find

I was browsing at a flea market over the weekend and stumbled across a treasure trove of old costume jewelry, including this brooch key. I'm guessing it's made of brass, but who really knows with flea markets? I also saw a wonderful vintage-looking watch pin that I was thinking I could turn into a charm for a necklace, but as I didn't have enough cash on me (and it didn't even enter my mind until it was too late that being at a flea market, I could've haggled), I ended up buying just the key. I don't know what I'm going to do with it yet, but I'm pretty sure it will make its re-emergence soon.