The work presented by Georgiannou et al. (2017) on geotechnical properties of a natural zeolite is an important contribution because there are not many published works on this subject. The authors mention some of the several studies with natural zeolites in other research areas, mainly in environmental applications such as waste-water treatments, soil–bentonite mixtures and in the improvement of cement and concrete properties. They also mention the existence of numerous engineering and industrial applications of natural zeolites in farming, fisheries, textiles and construction materials. This discussion will complement and comment on some of the results obtained by the authors and suggest that extra information would be useful in order to make a more comprehensive analysis.