"The banner depicts two miners both holding one safety lamp and globe of the world in the background. The slogan is in Welsh " Dosbarth Glo Carreg Gwaith Abercraf Mewn undeb mae nerth a heddwch" The translation is "Abercrave Lodge NUM Anthracite District Workers of the world unite for peace and Socialism".
Now we can wait for Jorge, cubillas et al to tell us if they got it right.
Looks like they did, at least one version is billingual:
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