Thanks for your reply Mary

I knew that various metals were mined on IOM. I didn't know about the slate though. Perhaps turning ones hand from coal mining to slate mining is possible. Almost all the males in my Graham family have mined coal. Even right up to the pit closures in 1982/83, four of my uncles were still at it. They worked at Parkside Colliery, Newton Le Willows.
Before that, their dad's were miners at Haydock and Collins Green Lancs.
I have never heard of our Graham men mining slate, but that doesn't mean it never happened.
Thanks for your suggestion Mary.
Regards
David