The experimental setup adopted for the synchrotron measurements. (a) A schematic diagram showing SAXS signals acquired at different rotational angles φ. (b) A µCT reconstruction of the sample with the rotational axis aligned to the radial direction shown in Fig. 1. In this sample, the normal to the main surface of the mineral particles is mainly parallel to the rotational axis of the sample. This allows particles to scatter the signal mainly along the vertical direction of the detector, which we analyze by integrating the signal within an angular sector of Δχ = 6°.