The relatively poor thermal stability of fluorozirconate glasses is a major factor preventing the realisation of their true
potential for fibre optic applications. A range of methods based on both isothermal and non-isothermal DSC techniques, which
can be employed to evaluate the thermal stability of fluorozirconate glasses, are described. The relevance of these thermal
stability criteria to the design of fluorozirconate compositions capable of yielding high quality optical fibres is discussed.