Contenders for the biggest job in commodity trading, the head of Glencore, will be on parade this week. Outgoing CEO Ivan Glasenberg wanted his successor to look “like me,” and the main aspirants do. Glasenberg announced last December his plan to retire in the next few years, firing the starting gun on a closely watched race. The three most likely choices are Gary Nagle, Kenny Ives and Nico Paraskevas. They’re barely known outside Glencore, however, and as the global metals industry descends on London for LME Week, miners, traders and investors will be jostling to find out more.