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Magnetite is an abundant magnetic mineral that commonly records the ancient magnetic field in a wide variety of rock types. When cooled below ≈124 K, magnetite undergoes a phase transition, called the Verwey transition, whose characteristics are highly sensitive to grain size and stoichiometry. Studying the Verwey transition thus yields information on the formation conditions and compositions of rocks. The transition is also stress sensitive, thereby opening an avenue to understanding a rock’s strain history; however, the reason for the stress sensitivity is poorly understood. In particular, the temperature of the transition decreases when measured under pressure, yet mostly increases upon pressure release. Moreover, the stress sensitivity of the transition as a function of dopant concentration, especially after pressure cycling, was never systematically tested. We addressed these issues in order to further develop magnetite as a …