Not one degree more, not one degree less: -18°C is the exact temperature so that the millions of seeds deposited in Svalbard can survive for centuries with all their properties intact. Any alteration, however minimal, could be the end of them. Their conservation conditions are extreme: the vault itself can withstand earthquakes, tsunamis or natural disasters, while the seeds are stored in the chamber inside airtight pouches that limit their metabolic activity and protect them from ageing. In other words, don’t fiddle with these Midi earrings too much; you won’t want to change their temperature and compromise the future of humankind!