Billiton acquired the Colombian Govt company`s 50% share in El Cerrejon mine in consortium with Anglo American and Glencore. This is one of the largest open-pit coal mines in the world. Mining operations began in 1985, at exactly the same time as the underground coal mines in the UK were closed and Cerrejon became a major supplier of coal to the UK.
http://www.minesandcommunities.org/article.php?a=6676
What happened next? See BHP 2001 and 2020 below