This difficulty in studying Ca 2+ with NMR arises due to the combined contribution of the extremely low natural abundance of the Ca active nuclei ( 43 Ca, 0.145% natural abundance, which contrasts with the 100% of Al and 4.7% of 29 Si) and its quadrupolar nature (spin -7/2). Furthermore, a low frequency probe is needed (frequency at 600 MHz/14.1T of 40.368 MHz) which hinders the ability to experimentally access this nucleus in facilities where only common broadband probes are available. On the other hand, 60-70% by mass of a conventional clinker corresponds to CaO, highlighting the pivotal nature of this element in cement science.