The Portland cement clinker consists of 95% calcium oxide, silicon, aluminium and iron and 5% impurities of magnesium, sodium, potassium, titanium, sulfur, phosphorus and manganese. From the combination of two or more of the main oxides, the constituents of the white clinker are formed, corresponding to alite(3CaO.SiO2 or C3S), belite (2CaO.SiO2 or C2S) and celite (Ca3Al2O6 or C3A), which give cement its characteristic properties. The fundamental properties of cement are its mechanical resistance, chemical resistance, the speed of reaction with water and the heat given off in hydration. In this work, the reactivity of an artificial mixture of white clinker, formed from alite, belite and celite prepared by flame spray pyrolysis was evaluated. The phases were characterized by X-ray diffraction, scanning electron microscopy and microcalorimetry, to evaluate their formation and reactivity. The characterization showed that during the synthesis of belite, a greater amount of the polymorph alpha was produced, with some impurities. On the other hand, the synthesis of celite allowed the production of the polymorph CII. The reactivity was evaluated by microcalorimetry.