The C3A doped with 2.5 wt.% of Zn did not show significant
differences in the morphology either, but it was noticeable
that the icositetrahedron contained more defects. The
EDS proved that C3AH6 contained only a little of the added
Zn. Instead there were regions with a very high concentration
of Zn, some of which were amorphous and seemed to
be a residue of the added ZnO. Another region with a high
concentration of Zn is shown in Fig. 7. The hydration product
consists of long branched needles. The EDS showed that
beside Zn, these needles contain only calcium. Therefore,
this compound is probably Ca(Zn(OH)3)2 · 2H2O, which had
already been found in the XRD pattern.