The Fe₃Sn₂ crystal looks like a patterned lattice where iron atoms sit at the corners of hexagons. Under normal conditions, their magnetic arrows are aligned neatly, like soldiers in a row. But squeeze the crystal, and the alignment breaks.

Under a pressure of about 20 gigapascals (imagine twenty elephants standing on your thumbnail), the lattice slightly rearranges. The magnetic arrows lose their former rigidity: some of them tilt, forming an intricate pattern. This tilted order persists even under strong compression, although it was previously thought that it would disappear.

Calculations showed that compression strengthens the interaction that causes the arrows to deviate from a straight line. It's like a taut spring that tends to bend sideways when compressed. This behavior opens a way to finely tune the magnetic properties of materials simply by changing pressure — without heat or chemistry.