Electron microscope images in secondary electron (SE) mode of magnetite grains in A0226 and C0242 particle surfaces. (a) Panoramic SE image of framboidal magnetite on the A0226 surface, showing micro- to nano-impact craters (highlighted by yellow arrows), granular surface morphology, and magnetite grains interconnected by a “cobweb” texture. (b) Panoramic SE image of framboidal magnetite on the C0242 surface, showing a pristine, smooth morphology commonly associated with phyllosilicate (phyl.) sheets. (c) High-magnification view of the area in panel (a), highlighting quenched splash ejecta feature on weathered magnetite. (d) High-magnification view of the area in panel (b), showing a smooth magnetite surface and associated phyllosilicate sheets. (e) Individual magnetite grain in A0226 exhibiting nanometer impact craters on a frothy surface. (f) Individual magnetite grain in C0242 showing a smooth surface on a phyllosilicate-rich matrix.