This RF Safe article discusses rouleaux formation (reversible red blood cell stacking) and proposes a speculative mechanism by which weak magnetic fields might influence red blood cell surface charge (zeta potential) via spin chemistry in heme-related radical-pair processes. The piece frames the idea as a mechanistic “what if?” rather than a direct claim that everyday phone use causes blood clotting, and it leans on general concepts from hematology and radical-pair magnetosensitivity (e.g., cryptochrome in animals). No new experimental data are presented in the provided text; the argument is largely theoretical and interpretive.