Guinea's exports of bauxite, a feedstock for aluminium, surged 39% to a record 48.6 million metric tons in the first quarter though regulatory crackdowns sidelined major operators, official data obtained by Reuters showed.Most of this bauxite was shipped to China, where aluminium production has recovered. In the first five months of the year, China produced 18.59 million tons, a rise of 4.0% from the same period last year…