Good link Jack
seeing that Ossy had mines until 1930, I have been inspired to google more.
Wikepedia has a list too
List of collieries in Lancashire 1854-present - Wikipedia, the free encyclopedia
I have always wondered where the Ossy mines were , because on moving here 6 years ago, a neighbour who is an industrial history fan, told me that the open land around our flats could not be built on due to old mineworkings being too near the surface,