respectively, from which SEM images were recorded (Ba0.6La0.4F2.4 in Figure b-d and La0.9Ba0.1F2.9 in Figure f-h). For both materials, it was observed that no individual particles are visible on the fracture plane, and the surface looks like a continuous bulk solid. Only some loose powder particles are visible on the surface of both samples, with some indication of few micropores remaining after compaction at 2 GPa. The edge of the pellet, i.e., the part of the pellet which was pushed against the PEEK, is broken down into loose powder (Figure and). It is also visible, that the center of the pellets experienced significant discoloration from the original white powder, turning dark grey to black. This colour change did not take place at the edge of the pellet, indicating that most of the major densification happened in the center of the pellet, while the edge received less pressure due to the deformation of the surrounding PEEK alignment tube. The most striking difference between La0.9Ba0.1F2.9 and Ba0.6La0.4F2.4 is the number of cracks and degree of delamination, which can be seen in Figure b) c) f) g) as a scale-like feature on the fracture plane. Here, Ba0.6La0.4F2.4 shows a higher number of those delaminations on the same area than La0.9Ba0.1F2.9. For La0.9Ba0.1F2.9.