With low thermal expansion coefficients, eucryptite (Li2O.Al2O3.2SiO2) and spodumene (Li2O.Al2O3.4SiO2) in LAS ceramic system show good thermal shock resistance. In this study, sillimanite or kaolin group silicate minerals and Li2CO3 were used as starting materials, and if necessary SiO2 or Al2O3 were added for making stoichiometrically formed specimens. By this process, eucryptite powders were synthesized and characterized. The powder mixtures of lithiumcabonate and silicate minerals calcined at 80$0^{circ}C$ for 2 hrs were made into powder compacts. $eta$-Eucryptite single phase was formed via intermediate phases of Li2SiO3 and LiAlO2 et al, by heating at 110$0^{circ}C$ or 120$0^{circ}C$ for 10 hrs from those powder compacts. When using the sillimanite group minerals, Virginia kyanite or andalusite was reacted to form eucryptite at 120$0^{circ}C$and CMK International kyanite were completed at 110$0^{circ}C$. When kaolin group minerals were used, it was found that the synthesizing temperature (100$0^{circ}C$) of $eta$-eucryptite from the mixture of New Zealand white kaolin was lower than that from Hadong pink kaolin (110$0^{circ}C$). The Microstructure of systhesized powder showed the irregular lump shape such as densed crystallines.