Subscribe To My Youtune Channel For 210+ Coal Mine Tributes And Counting. Seaham Colliery "The Nack" Sunk 1845 and sadly closed 1987. Colliery was a coal mine near Seaham in County Durham. Sinking of the first pit began on 13th April 1849 for the by the third Marquis of Londonderry. In the late 19th century, the colliery was producing between 2,500 and 2,800 tons of coal per day, which were shipped at Seaham Harbour and Sunderland Dock. The mine suffered an underground explosion on the 8th September, 1880, which resulted in the deaths of 164 men and boys. At it height, in 1914, the colliery employed 2,574 people below ground and 520 above ground.The mine was nationalised in 1947 and in 1988 was merged with Vane Tempest colliery, and was closed by 1993. The King of Spain Alphonso X111 visited Seaham Colliery in 1929.