As seen at Swansea 🏴󠁧󠁢󠁷󠁬󠁳󠁿 National Museum:

At the end of the nineteenth century Wales was one of the most important coal producing countries in the world. At its peak industry employed around quarter of a million people. With over fifty million tons of coal being produced from around 600 collieries.
It was once the most important industrial, social and political forces in modern Wales.
Today the industry has all but vanished.
William John 'Chopper' Davies was born in Nantyglo.
At fourteen he went to work in Beynon's Colliery.
He was working in Six Bells Colliery in 1960 when an explosion killed forty five men.

©Amgueddfa Cymru National Museum Wales