The thermal properties and devitrification behaviour of substituted InF3 glasses were studied by means of differential thermal analysis. A comparison of various simple quantitative methods to assess
the level of stability of multicomponent fluoride glass systems was also made. Most of these methods are based on critical
temperatures. In this paper, a new parameter,kd(T), is introduced to the stability criteria. The stabilities of several substituted InF3 glasses were evaluated experimentally and correlated with the activation energies of crystallization via this new kinetic
criterion and compared with those evaluated by other criteria.