A mixed alkali germano-phosphate glass composition (Li0.5Na0.5Ge2(PO4)(3)) has been prepared and characterized. The crystallization mechanism of a NZP-type phase, the nucleation rate and the non-isothermal kinetic parameters have been studied by differential thermal analysis (DTA). The plot of the DTA peak height versus the glass particle size has shown a great tendency for surface crystallization. The nucleation rate type curves have given a maximum at 465 +/- 2 degrees C and confirmed that nucleation was instantaneous at this temperature. Furthermore, the average value of the Avrami exponent (5.4 +/- 0.4) has revealed a tri-dimensional growth controlled by the development of the glass-crystal interface with a decreasing nucleation rate in the temperature range explored. From non-isothermal experiments, the apparent activation energy for the overall crystallization phenomenon has been founded in the range 260-273 kJ/mol whereas the activation energy for crystal growth was 488 +/- 6 kJ/mol. (C) 2006 Elsevier Ltd. All rights reserved.