Lucy Thomas (née Williams, baptised 11 March 1781 – 27 September 1847) was a Welsh businesswoman and colliery owner known as the "mother of the Welsh steam coal trade". Thomas took over the running of her husband Robert's coal mine after his death in 1833. Unusual as it was at the time that a woman ran the business, more unusually she was also illiterate. Business documents held in the Glamorgan Archives show she signed only with an X. Much of Thomas' subsequent success as a businesswoman was embellished by Merthyr historian Charles Wilkins, who wrote one of the few articles on her life. It is now believed that George Insole, a Cardiff agent, was one of the chief architects of her success, though this does not diminish Thomas's position as one of the few women coal owners in industrial Britain. It is recorded that Lucy once attended the Coal Exchange in Cardiff only to be told she could not enter. She sent a male clerk in her employ into the Coal Exchange with a letter informing the establishment that "My coal is equal to any mans, failure to grant entry will lead to my business lining another's pockets." Background Lucy Thomas (née Williams) was baptized in Llansamlet, south Wales, on 11 March 1781, the daughter of Job Williams and his wife, Ann James. She married Robert Thomas at Llansamlet on 30 June 1802. Robert was a contractor of a coal level, providing fuel for Cyfarthfa Ironworks. They had eight children, six sons and two daughters. As an industrialist In 1824, Robert Thomas took up an annual tenancy from Lord Plymouth for the opening and mining of a small coal level at Waun Wyllt, near Abercanaid, south of Merthyr. The contract forbade Robert Thomas from trading with the four local iron-works which were under the ownership of Lord Plymouth. Although little was expected from the level, it was the first to hit the "Four Foot Seam", a rich deposit of high quality steam coal. The mine initially sold its coal to local households in Merthyr and Cardiff, with a tramline being constructed from Thomas's level to the Glamorganshire Canal to allow transportation to Cardiff Docks. Robert shipped his coal along the canal to Merthyr from July 1828 and to Cardiff from February 1829 (in particular, Robert supplied Richard Biddle, a Cardiff trader, from that month). In November 1830, George Insole (in