B. Hoghooghi, J.M. McKittrick, C. Butler, E. Helsel, and O.A. Lopez, "Near-Net-Shape Forming of Celsian Ceramics from Ion-Exchanged Zeolite Precursors," Materials Research Society Symposium Proceedings, 346 (1994) 493-498.

A technique has been developed for the synthesis and near-net-shape forming of celsian glass-ceramics. This technique involves ion exchange of zeolite precursor powders, heat treatment of the powders to temperatures between 800-900°C to form a glassy phase during which the samples are formed under low stresses (<20 MPa). Upon further heat treatment to about 1000°C, crystallization occurs and the amorphous formed body is transformed to the celsian ceramic phase. Using this technique, and through the addition of monoclinic seed particles as well as a mineralizer, monoclinic celsian was produced at temperatures as low as 1000°C at heat treatment times of less then one hour. This forming technique also resulted in a significant reduction in the porosity of the ceramic bodies compared to free-sintered samples.