Lithium disilicate glass (Li₂O•2SiO₂) is a considerably studied composition and has been considered a model for glass-ceramic. Taking its stoichiometry as a base, this work tried to study new compositions replacing SiO₂ with GeO₂, or just adding it to the mixture, as both oxides are good glass formers. One composition was made just replacing one mol of the silicon oxides with a germanium oxide, thus having the stoichiometry Li₂O•SiO₂•GeO₂, X-ray diffraction (XRD) confirmed that glass is formed in this composition. Differential thermal analysis (DTA) show Tg in 470°C and Tc in 560°C, with a very intense crystallisation peak exothermic. For the High Pressure processes, toroidal type chambers were used up to 7.7 GPa in controlled temperature. After a fusion of glass in 7.7 GPa we used Raman spectroscopy to analyse the sample, the results indicate the vibrational modes in 303 cm^-1 characteristic of  Germanium, probably segregated from the rest of the composition, further structural analysis with XRD are being performed. When submitted to a crystallisation treatment to form glass-ceramic in atmospheric pressure, the phase formed is probably a solid solution of Lithium Disilicate glass-ceramic with some Germanium atoms occupying the Silicon positions in some spaces.Thermal treatment in high pressure to form glass-ceramic will be performed and the results will be compared to those made on atmospheric pressure. The effect of the densification without using high pressure and room temperature is also being analysed by means of DTA, XRD and Raman spectroscopy.