Standard rock magnetic measurements and domain wall resonance measurements for magnetite are combined in an attempt to define better how domain walls are pinned and how such pinning is related to magnetic stability. Using these two different measures of stability, before and after annealing at 650¿C, we find that domain walls are primarily pinned by dislocation arrays. Tightly pinned walls can exist in grains that show relatively low values of coercivity, indicating that magnetic screening can play a critical role in determining the properties of remanence.