This chapter examines the characterization of calcium aluminate cements (CAC) with 52wt% and 71wt% of alumina content. Cement paste samples were fabricated at 0.4 and 0.5 water to cement (w/c) ratios. The microstructure of both the raw cement powders and their corresponding samples were characterized after hydration by scanning electron microscopy, X-ray diffraction (XRD), X-ray fluorescence (XRF), granulometry, density and compression tests. The main disadvantage of the CAC is that strict control of parameters and variables such as water or cement ratio, temperature, humidity and grain size is required during the hydration process. The fine-textured grains are mainly due to a faster cooling rate during the manufacturing of the cement, while the coarser-textured grains result from a slower cooling rate. The mechanisms involved in the physico-chemical process during the hydration of calcium aluminates are not fully understood because they depend on many factors that are difficult to control, such as mixing time, temperature, water/solids ratio, particle size, curing humidity conditions and the presence of alkali.