Almost all mixtures contained arcanite (K2SO4), a mineral
known to be a setting accelerator of cement. A significant amount
of anhydrite was still present in the reference mixture (without HT
treatment). H2O HT treatment also left a small quantity of anhydrite.
Some particular minerals were found in the different mixtures:
kaliophilite-type mineral (KAlSiO4) in KOH HT cement and ternesite
(Ca5(SiO4)2SO4) in cements obtained with and without H2O
HT treatments. A small quantity of yeelimite (Ca4Al6SO16) was also
detected in the reference mixture.