We reveal that for mixtures of different ions, something extraordinary occurs. Instead of forming a single flawless crystal, the matter can organize itself into so-called spherulites—mesmerizing, spherical structures that sprout like tiny sea urchins or coral heads under the microscope. They uncovered how subtle shifts in ion composition—specifically, the presence of so-called divalent ions in highly viscous mixed sulfate solutions—drive the formation of well-organized sodium sulfate nanocrystals into spherulitic shapes at room temperature.

Tess Heeremans et al, Controlled spherulitic crystal growth from salt mixtures, Communications Chemistry (2026). DOI: 10.1038/s42004-026-01892-0
Link IoP: Spherical assemblies of nanocrystals – IoP – University of Amsterdam