Diamond billionaire Nicky Oppen-heimer is retiring as non-executive director of Anglo American, after 37 years with the company.

The South African's announcements brings an end to an era for the firm, one of the world's largest mining companies, which was founded by Oppenheimer's grandfather Sir Ernest Oppenheimer as there will no longer be a family member on the board.

Nicky Oppenheimer, 65, is also chairman of De Beers, but is reported to have said that his decision to leave "has nothing to do with his family's commitment to De Beers".

Oppenheimer will step down from the board at Anglo American's annual general meeting to be held on 21 April 2011.