In cold sintering, there are diverse pathways to obtain dense materials(Fig. 3). In the first pathway, which is the most commonly used, a compound A leads to the same compound A (A→A) as the initial powder and the final material are of the same composition and crystallographic phase. Alternatively, there is a pathway where a compound A leads to a compound B (A → B), where the final material has a different chemical composition or crystallographic phase than the initial powder. Finally, there exists the possibility for Aþ B→C, which is a reactive route, where a mixture of compounds A and B can whether lead to a chemical doping or to a new compound after CSP.