Newly released papers from Margaret Thatcher's time at Number 10 have shown she may have planned to close over 70 pits.
The secret "hit-list" means that the government may have been looking at a further 50 closures than the 20 that were talked about by the government and National Coal Board.
The document reveals they wanted to close the mines over a three year period.
Arthur Scargill, then leader of the Yorkshire National Union of Miners, had always claimed the government were planning to close more mines than were being discussed publicly.
More top news
A former member of the far-right party is standing for the seat
The Batley and Spen MP was due to launch the report, by the charity Tell MAMA, today
Rebekah Tiler has been lifting since she was 12