The dataset of 3D structures and their corresponding 2D images was created using Blender [3], an open source computer graphics suite used for 3D modeling, rendering, animation, and scientific visualization. In this dataset, powders are comprised of spherical particles with sizes drawn at random from the appropriate PSD. We consider eight PSDs, as shown in Fig. 1, and construct 256 independent structure/image pairs for each PSD, resulting in 2048 synthetic powder micrographs (examples are shown in Fig. 2).