The fitting parameter a is related to the number and geometry of particle-particle contacts in the percolated network, and b is related to the bond stiffness between the particles. Thus, equation 1 captures the different micro-structural and mechanical properties of chemically different hydrate phases. We fit the storage modulus development using equation 1 in the first 3 h of hydration (Supporting Information Figure ). The poor fit of equation 1 to the experimental data reveals that the development of the storage modulus can not be described using a single exponential function.