A rather simplistic answer that, no context to it.
Since WW2 the Tories shut far more mines than Labour. After WW2 Labour nationalised the Coal industry as it was seen as vital for our energy needs. They inherited an industry that had suffered woeful underinvestment and duly invested in the industry. When the Tories came back to power they scrapped the labour plan to make the mines cost effective and left them in such disrepair there was no choice but to close them and consolidate the industry. Thatcher closed mines out of spite, she hated the Unions and thought that by beating the NUM she could bring down Union power. Other factors came into play of course such as the advent of nuclear power and oil fired power stations lessening the need for coal and in todays world coal is no longer a viable energy source because of environmental concerns.