Project Halo – the consortium which came out as the preferred bidder in the highly-contested purchase of coal mine previously owned by the Gupta family – on Tuesday rejected allegations of impropriety in the way it secured the bid to acquire mine and other related assets. Last year, Project Halo won a bid to buy Optimum Coal Mine, Koornfontein Mine, and Optimum Coal Terminal in Mpumalanga for R3.6-billion from Tegeta Exploration and Resources, a mining company which is linked to the controversial Gupta family.