It has to be borne in mind that some phases predicted by chemical reactions, such as AH3 or CH, were not detected as crystalline phases. AH3 reacts with belite to give some crystalline phases discussed above. In any case, the remaining AH3 and a very small amount of CH were considered as ill-crystallized phases and included as C-A-H or C-S-H amorphous gels, respectively. These amorphous gels have been detected by cryo-SEM, arrow in Figure 3-right.
3. Conclusions The main goal of this contribution is that it has been quantitatively demonstrated that 'H-C2S belite polymorph can be stabilized by borax in belite sulfoaluminate clinkers and that this polymorph hydrates much faster than -C2S polymorph.