 They controlled most of the islands centers of wealth, as well as much of its trade and resources.In Wales the known tribes (the list may be incomplete) included the Ordovices and Deceangli in the north, and the Silures and Demetae in the south.Archaeology combined with ancient Greek and Roman accounts have shown that there was exploitation of natural resources, such as copper, gold, tin, lead and silver at multiple locations in Britain, including in Wales.