London: Varda Shine, the former CEO of De Beers’ sales arm, the Diamond Trading Company, has joined the board of miner Petra Diamonds as an independent nonexecutive director, the London-based company announced.

Since she left De Beers in 2013, Shine has become a board director at two other mining companies, Lonmin and the Mineral Development Co. Botswana, which is owned by the government of the Republic of Botswana. She also serves as a director for equipment manufacturer Sarine Technologies.

Shine is also a governing board member of the Diamond Empowerment Fund (DEF) and a trustee of the Teenage Cancer Trust. In 2011, she received the Women’s Jewelry Association’s Hall of Fame Lifetime Achievement Award, and she was the first woman awarded honorary lifetime membership of the Israel Diamond Exchange.

Most of Petra Diamonds’ mines and assets once belonged to De Beers, and it has prided itself on making those assets, sometimes considered past their prime, economically viable. It started by purchasing the South African Koffiefontein mine from De Beers in 2006. It then bought the Cullinan in South Africa in 2007; the Williamson mine in Tanzania the next year; the Finsch mine in South Africa in 2011; and the Kimberley mine, also in South Africa, in 2015.

Also appointed as Petra nonexecutive independent director was Bernard Pryor, a metallurgic engineer with more than 35 years’ experience in the mining business. He is currently CEO of Alufer Mining and nonexecutive chairman of MC Mining Limited. He was previously CEO of African Minerals Limited and Q Resources.

Last month, Petra CEO Johan Dippenaar, who had been with the company since its 2005 merger with Crown Diamonds, announced he was stepping down after 13 years with the company. A successor has not yet been named.

In a statement, Petra said it was “further reviewing and optimizing the composition of [its] board” and plans to “improve diversity at the higher levels of the business.”