The strongest permanent magnets today contain a mix of the elements neodymium and iron. However, neodymium on its own does not behave like any known magnet, confounding researchers for more than a half-century. Physicists at Radboud University and Uppsala University have shown that neodymium behaves like a self-induced spin glass, meaning that it is composed of a rippled sea of many tiny whirling magnets circulating at different speeds and constantly evolving over time. Understanding this new type of magnetic behaviour refines our understanding of elements on the periodic table, and could eventually pave the way for new materials for artificial intelligence. The results will be published on 29th of May, in Science.