Anyway, last time he used it a shard of glass came off the rim, and now it no longer spins properly. I want to find him a replacement, but I have no idea what such a thing would be called. He got it as a child and doesn't know its name. I tried googling and using image search, but had no luck. I'm guessing it would be sold as an ornament / paperweight rather than as a children's toy, but I really don't know.
So: does this object sound familiar to anyone, and does anyone know what it would be called? Thanks in advance!