Comprehensive mineralogical study of Australian zeolites

Industrial applications of natural zeolites depend on their mineralogical, physical and chemical characteristics. Over the last 20 years, Australian natural zeolites have been investigated for use in various industrial applications. However, there are few, if any, mineral characterisation studies on Australian natural zeolites since the early 1990s that use modern techniques. In this study, a detailed mineralogical analysis was conducted on zeolite specimens from Avoca and Werris Creek deposits, located in Queensland and New-South-Wales, respectively, in Australia. Their physical properties, thermal behaviour and porosity, as well as mineral compositions were determined by conventional methods, including thermogravimetry, N2 adsorption/desorption, optical microscopy, XRF, in situ XRD, SEM/EDS and EPMA/WDS. High-precision, high-accuracy measurements of the chemical compositions of fine-grained zeolites (<20 μm) were performed in situ in thin section using accepted EPMA protocols and data reduction methods. The Australian zeolites were identified as magnesium heulandite/clinoptilolite-Ca which corrects interpretations from earlier studies.