Some considerations and comments can be mentioned for thermal properties. Serrano-Lopez et al. (2013) reviewed the complexity of thermal properties measurement in the case of molten salts, especially at high temperatures. For example, different problems may appear in the case of thermal conductivity, introducing external factor that change ideal measurement conditions: method of measurement election, sample homogeneity, sample purity, thermal stability at high temperatures, interaction between sample an containing material, sensor ranges for measurement, or other heat transfer mechanisms such as convection and radiation. Any of these variables may introduce erroneous values in the measurements, and even estranges slopes in the correlation functions (as has been reported for nitrates or chlorides, for example). On the other hand, different theoretical-estimation methodologies have been also proposed for conductivity prediction. Although some of these empirical expressions were deducted for particular type of mixtures, Serrano-Lopez et al. (2013) tried several of them with other compositions to check its potential use. In the case of FluZirK, for example, there was not any measurement for thermal conductivity (at least till 2013), and this kind of predictive equations were the only way to make an estimation. In a global comparison, Rao-Turnbull predictions give acceptable values (but the expression is very sensitive to the average number of ions per mole used in the calculation). Also in a global comparative, there seems to be relatively low temperature dependence for most of mixtures. Only certain values for FLiNaK are anomalous if compared with the others. For other thermal property like Heat Capacity, there is also a certain lack of data and scattering. No measurements have been identified for FluZirK, for example (at least till 2013); therefore only estimations with empirical correlations can be made in this case. (See also Serrano-Lopez et al., 2013)