A mixture of 69 wt% C2S/31 wt% TCP was prepared. First, TCP and C2S powders were ground to an average particle size of ∼20 μm, and the desired proportions of each component were weighed in an analytical balance and thoroughly mixed with PSZ-zirconia balls. After drying, the samples were isostatically pressed in bars at 200 MPa. Pellets obtained from the bars were put into small platinum foil crucibles that were suspended from a platinum wire in the hot zone of an electrical furnace with an electronic temperature controller (±1 °C). The pellets were heated up to 1550 °C for a total period of 144 h (6 days), with quenching in liquid-nitrogen, milling, pressing and reheating every 24 h.