The Cobre mine was a copper mine in Cuba, the oldest in the new world. The open pit mine was operated from 1544 to 1998.The Spanish used slave labour and free coloured labour to work the mine.After it had been abandoned, in the 19th century a British company acquired the mine and reopened it, again using slaves and free coloured labourers, but also using skilled Cornish miners and steam engines from Cornwall to operate pumps. The mine was abandoned again, then reopened by an American company at the start of the 20th century. After the Cuban Revolution it was taken over by the state.After being finally abandoned the pit is now filled with a mineral-rich lake.