Different crystalline phases (tetragonal zirconia, titanite, celsian, diopside, anortite, zircon, scheelite, casiterite, gahnite and spodumene) have been devitrificated into a transparent ceramic glaze by addition of oxides that acts as crystallisation agents. Microstructure, wear resistance and gloss of glass ceramic surface obtained on fired modified glazes are studied. All crystalline phases diminish the brittleness index of the original transparent glaze. Anortite stands out among reinforcing phases that produces dull surfaces associated with high roughness. On the other hand, zircon stands out among the phases that improve gloss surface together wear resistance.