I appreciate the comments. I am not convinced it's a Bennington or even German. All I know is that I haven't seen too many like it - maybe one or two, and nobody else seems to know much about them either, so I'm not sure what to think about it.
I don't think there is a name associated with it and the more I look at it the more Vitro it looks to me, so I don't know what to think about it, other than that it looks like a veneered marble.
Sorry, not much help, I know. lol
It's a slag. Are there any cut lines that you can see? The large, sort of oval, reflection that covers the top half of the marble in every pic makes it hard to see if there are - the reflection itself can look like a seam.