2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/25485We present magnetoresistance and Hall-effect measurements on single crystal magnetite Fe3O4 close to the Verwey transition Tv = 123.8 K. We show that the formation of grain boundaries accompanying the reduction in crystal symmetry plays a significant role in the electron scattering mechanism, and that grain boundaries can account for the apparent change in sign of the charge carriers below Tv.7 pages, 3 figures, Included in the proceedings from the 49th Annual Conference on Magnetism and Magnetic Materials, AIP number 188510JAPStrongly Correlated ElectronsOther Condensed Mattertext