Dr. Greg Stone speaks with his two colleagues, Dr. Steve Katona and Diana Palikas about their recent collaboration on a white paper entitled ‘Where Should Metals for the Green Transition Come From?’. The document breaks new ground by exploring the environmental, social and economic costs of different sources of base metals required to transition the world away from fossil fuels. The conversation touches on the fact that polymetallic nodules are made of almost 100% usable minerals and contain no toxic levels of deleterious elements, compared to ores mined from the land which have increasingly low yields (often below 1%) and often do contain toxic levels of deleterious elements. Fair disclosure: Dr. Stone works for The Metals Company who funded this paper.