Mike Reynolds, Betws lodge secretary of the National Union of Mineworkers, said: 'It's important for the survival of the language that it should continue to be spoken at the workplace.'
But Betws has reserves to exploit of more than Celtic culture. Opened in 1974, its tunnels slant in to seams like the Red Vein and Peacock, reserves of anthracite that pit managers and workforce agree have a profitable long-term future British Coal cannot see.
Betws is one of 10 collieries earmarked in the October hit-list of 31 pits for imminent closure. It continued to work its one production face until exhaustion on Wednesday. From Monday, the 112 men will join the demoralising regime of clocking on and being sent home to which miners at the remaining nine pits have become used. And while Welsh anthracite lies undisturbed, the Humberside port of Immingham will be busy with imports of Vietnamese anthracite, bought by British Coal at prices Betws believes it can beat.
Anthracite is the hardest form of coal, the cleanest to mine, and the greatest energy source. It keeps home fires burning and, according to the colliery managers' union, BACM, it has promising new export markets for water filtration which British Coal has failed to exploit. If closure is confirmed by the Government, BACM will attempt a management-employee buyout of Betws. A union document accuses British Coal of bad mining engineering and even worse marketing.
The document claims two-thirds of Betws's weekly output of 3,000 tons has been sold to power stations, which do not need the high calorific value of anthracite.
'This is a waste of premium fuel,' the BACM document says. It is also a waste of public investment in the mine. Anthracite sold for domestic use earns Betws pounds 80 a ton; power stations pay less than half that, and the filtration market would pay up to pounds 200 a ton. 'The problem has been British Coal's insistence on using the same mechanised, longwall mining methods at Betws that are used in other mines,' Mr Reynolds said.
South Wales NUM doubts whether British Coal wanted to make a success of anthracite mining. The state-owned corporation is majority shareholder in a coal factoring company that buys anthracite from private, opencast pits.
Last year, British Coal moved the goalposts of competition to its own disadvantage, omitting from operating licences a clause which stipulated that private mines should employ men under terms and conditions comparable with British Coal's own pits.
'The industry has been deregulated. Men in private mines have been sacked, then re-employed on worse terms. Wages and safety standards are being whittled away,' Mr Reynolds said. The union hopes Parliament will reverse the closure decision, enabling the 13 weeks of development work needed to bring a new face into production to begin.
British Coal said mining Betws's remaining coal was not feasible. 'The domestic market is extremely competitive, and anthracite particularly so,' a British Coal spokesman said.
'We have to compete with other fuels, including imported anthracite. We have to face that challenge, not bury our head. In real terms our prices are 30 per cent lower than in 1988.'
British Coal planned to increase production from opencast sites and rejected claims that the wrong mining techniques had been used at Betws.
'We're not prepared to go into discussions about the rights and wrongs of decisions taken at Betws,' the spokesman said. Unions and management at Betws believe their pit will sustain a feasible business. But unless changes can be wrung from the Government, vernacular pit Welsh may be a dead language. Tools ar y bar, Betws - and they may indeed have hung up their tools for the last time.