The preparation of the 11.7Li(2)O-39.7WO(3)-10.9CaO-37.7P(2)O(5) glass (pgLWCP) was based on a one-step heat treatment of the 6Li(2)O-18WO(3)-43CaO-33P(2)O(5) (gLWCP) glass followed by leaching of the beta-Ca2P2O7 phase formed during the crystallization process. The porous structure was formed in the region formerly occupied by the beta-Ca2P2O7 phase. The gLWCP undergoes devitrification through surface crystallization. This process occurs after a thermal treatment in lower temperature and in a shorter period of time than that required for the complete crystallization. After acid leaching treatment, we obtained a core/shell-like structure with a very well-defined dense glass (gLWCP)/porous glass (pgLWCP) interface. The pgLWCP exhibits reversible coloration-decoloration reactions. (C) 2010 Elsevier B.V. All rights reserved.