In Eric Cline's 1177 BC, The Year Civilisation Collapsed he notes that the Mediterranean civilisation's principal source of tin was in Afghanistan. Given how important tin was to a bronze age civilisation (Cline compares it to the modern day focus on oil), do we know how this trade actually functioned?

For example, who was mining the Afghani tin and facilitating its transport westward to the Mediterranean? Do we know if there were ever attempts by e.g. Assyria to restrict/bottleneck the supply to put pressure on their more western neighbours?

Thanks for reading