"My Grandfather, John Edmund 'Jack' Harris of White Hart, Machen worked at Bedwas Colliery. At the end of the second week he complained that his pay packet had been below the minimum wage for both weeks. After being told to wait, the Wages Manager came back and said 'There's your minimum wage - and here are your cards'. "
A blackleg was the slang expression for non union labour often taken on by collieries who were fighting hard to stop trade unions in the mines. The "blackleg" was usually a miner who had been dismissed from another colliery and was desperate for work, and accepted employment in place of striking workers. The "blackleg" was despised by the union workers as they took their livelyhood. The origin of the term dates from times when most mines had limited wash facilities at the pit and workers would only wash their hands and face. So a strike-breaker could be picked out during a strike as someone who left the pit at the end of their shift with clean hands and face but "black legs"