By Polina Devitt LONDON (Reuters) -Global commodity trading house Gunvor is expanding its precious metals business from trading derivatives into physical metal and has hired specialists in the London and Singapore trading hubs, the company told Reuters. Gunvor's expansion in the sector coincides with a rally that has seen gold prices rise twofold since late 2022 as investors sought shelter from global economic and geopolitical turbulence. Spot gold hit a record high of $3,674 per troy ounce on Tuesday. G ...