Thomas Coster and Co
1736/7 The White Rock Copper Works were established in the Lower Swansea Valley by John Hoblyn. The works were operated by Thomas Coster and Co. Hoblyn later married Thomas Coster's daughter. White Rock was one of the most important copper smelting works in the Lower Swansea Valley, which was the world centre of non-ferrous smelting for much of the 18th and 19th Centuries. It was the third of Swansea’s copper works to have been built.