Labour closed more mines than the Conservatives did
Between 1963 and 1979, Labour governments closed a total of 303 collieries. Successive Conservative governments shut 162 mines. Even the left-of-centre Energy Minister, Tony Benn, recognised the economic argument and closed more coal mines than Margaret Thatcher and Michael Heseltine put together.
Yet those 162 mines the Tories closed accounted for more job losses than the closure of the 303 that Labour closed.
You have to look at this from pit closures and job losses. Labour closed down the smaller ones, Tories closed the bigger ones.
Still doesn't alter the fact that the mines were losing 1.1 billion quid each year which, back in those days, was a hell of a lot of money. And the unions stepping in to shut production down in a strike that only had 30% backing thus making the mines that could open even more unproductive.