When studying the _10-250’ isotherm of Fig. 4, it is evident that the amount of copper retained does not change much in the time interval from 5 to 20 min. Hence, a third possible strategy for avoiding desorption lies in separating the copper loaded olivine flour from the iron containing solution within this narrow interval. In practice, separating solid from liquid within a time span of 20 or maybe 30 min represents a considerable challenge. However, if achieved, the chemical potential of the process could be fully utilised without introducing other chemical mechanisms. In consequence, such a system could prove to be more robust.