Thread: Combo Coticule, or coticule on slate?

I was looking at getting a coticule, and was looking at a vintage one. I wanted another pair of eyes to look at it. not sure if its coticule on slate or if its a combo stone, i don't see a glue line so I'm thinking combo

Coticule side seems a little thin compared to some of the modern ones Ive looked at. but grain texture looks nice and creamy.