Leucite (K₂O·Al₂O₃·4SiO₂) converted from geopolymers as a sustainable approach, was used as an alternative to feldspar, one of the three components of dental ceramics. Leucite crystals were obtained from a dried potassium geopolymer of the composition K₂O·Al₂O₃·4SiO₂·11H₂O by heating at 1200 ^oC for 3 h in an open-air furnace. Produced leucite was crushed into small parts, powdered in a planetary mill and then sieved to sub-63 micron size. Leucite crystals were then replaced by feldspars at a range from 0-100 (wt.%) in all three parts of dental ceramic slurries. The slurries were molded to 1 cm³ and subsequently heat-treated at 1300 ^oC-1450 ºC/4.5 h with a heating rate of 10 ºC/min. Final products were microstructurally characterized with XRD, SEM-EDS and mechanically based on Weibull analysis of compressive tests. Due to the phase transformation occurring in leucite, it was determined that the amount of leucite had a significant effect on the structural integrity and therefore the mechanical properties of the final dental material. Results of the statistical analysis showed that the replacement of 50% leucite exhibited the highest compressive strength of (49.3±10.5 MPa) compared to the other samples consistent with microstructural analysis

Keywords: Geopolymer, Leucite, Dental Ceramics