development of sealing mortar for road works ; acceleration of self - leveling topping mortar based on CAC . Yeeli mite or Klein 's compound ( anhydrous calcium sulfoaluminate , 4Ca0.3 Al2O3S03 ) is the key ingre- dent of CSA cement . Its importance derives from the fact that on hydration in the presence of lime and calcium sulphate , it rapidly hydrates to form ettring ite , leading to high early strength development .