In this work we present and highlight the potential benefits that QCr and other quantum-experimental techniques could bring for the study of HPEs. We will do so by focusing on the case of Ca-sc, or Ca-III . This cubic phase of calcium has been observed forming at pressures greater than 35 -40 GPa from Ca-bcc (Ca-II) over a wide range of temperatures, from 300 K to 800 K (it is possible that Ca-sc exists also at higher temperatures, since the melting point of Ca at 40 GPa is ~2000 K). It was soon hypothesized that Ca undergoes a pressure induced s-to d-electronic transition . In fact, it was predicted that the strongly hybridized s-and d-orbitals of Ca form a MCB inside the cubic Ca8 cavity, which corresponds to the generation of the electride state in this system . The MCB mechanism was also proposed by in a previous work based on theoretical topological analyses . However, as any other HPE, the electride state is, so far, only inferred theoretically.