Deco Black Glass Vase UPDATED

Found this in an antique shop in an old barn. It's 8 3/4" tall and about 4 1/2" at the widest point. There are some scratches on the bottom, showing it has some age. If anyone has more information on what it is, please let me know. Thanks!
Update:
I found a mark! It looks like IPG inside a triangle, located near the base. I believe this is the Illinois Pacific Glass Co. I've seen their mark on a couple of different pages. Most of the references I see are for utilitarian ware, like bottles and jars. This is definetly an art glass piece, maybe some kind of experimental. The mystery deepens!