Rio Tinto will share the windfall of its copper bonanza with shareholders after reporting a massive surge in first-half net profit that was underpinned by production growth of the red metal. Chief executive Simon Trott described the first half of the year as “a step-change” in performance. Get the first look at the digital newspaper, curated daily stories and breaking headlines delivered to your inbox. It is targeting full-year production of between 800,000t and 870,000tIron ore still remains the group’s biggest earning, but now only just. Sales from its massive Pilbara network hit 157.7 million tonnes while its Simandou mine in Guinea contributed 400,000t as the project continues to ramp up.