I found this in an antique mall. I think it would be cool to have one of these but I didn't buy it mainly because I don't have a good idea what something like this is worth. It seems to be in pretty good shape. I hadn't seen glass this shape or color before, but that's not saying much because I haven't looked at a lot of them either. The glass seemed thicker and less fragile than the typical round glass balls I'm more familiar with.

Could someone give me a ballpark on what this might be worth? Thanks!