The desired esthetic effect was obtained using coarse frits with crystallization in their boundaries that was capable of generating visual contrast with the particles in the bulk. The esthetic effects change the characteristics of the frits in the range between their crystallization and melting temperatures. A lower heating rate contributed to the visual contrast observed between the boundaries of the frits and the matrix and to the reduction of the superficial porosity. The holding time at the maximum temperature contributed to increasing crystallinity and decreasing bulk porosity in the material.