Welsh Associated Collieries
1929 Cambrian Collieries Ltd merged with other coalmining companies to form Welsh Associated Collieries
1930 28 January: Agreement between shareholders in Gueret, Llewellyn and Merrett Ltd., D. Davies and Sons Ltd., Bwllfa and Cwmaman Collieries Ltd., Llewellyn (Nixon) Ltd., Llewellyn (Plymouth) Ltd., Llewellyn (Cyfarthfa) Ltd., Troedyrhiw Coal Co Ltd., D.R. Llewellyn and Sons Ltd., The Aberdare Graig Coal Co Ltd., The Duffryn Rhondda (1929) Ltd., The Cynon Coal Co. Ltd., and Guest, Keen and Nettlefolds Ltd., to amalgamate forming Welsh Associated Collieries[1].
1936 Welsh Associated Collieries were absorbed into the Powell Duffryn Associated Collieries.