Former Anglo American executive director Simon Thompson, 58, has been appointed chairperson of diversified mining company Rio Tinto, where he has served as a director since 2014. Thompson will, from March 5, succeed South African-born Jan du Plessis, who held the post since 2009. The outgoing chairperson has reaffirmed that the company is working with authorities on regulatory investigations relating to its operations in Guinea and Mozambique. The US Securities Exchange is conducting an investigation relating to the impairment included in the 2012 accounts over the Rio Tinto Coal Mozambique operations, acquired in 2011 and sold in 2014.