The experiment wishes to measure the strain profiles across 12 mm thick reference ceramics slabs especially produced to minimize and maximize thermal stress during cooling. The strain profiles determined in different portions of the samples will be used as references to calibrate the fringes effects observed on the same samples by digital holographic speckle-pattern interferometry (DHSPI). It is expected that the neutron data will allow anchoring absolute values of strain to the relative strain observed by the density of the DHSPI interference fringes. If the calibration is effective, it is expected that DHSPI may be proposed as a routine test to detect accumulated strains in ceramic bodies in field/operating conditions.