Abstract: The present invention provides zinc-free glass frits that can be used to formulate glaze compositions that develop glossy surfaces when fired on ceramic products such as floor tile and wall tile. The zinc-free glass frits include, by weight, from about 50% to about 70% SiO2, from about 5% to about 20% CaO, from about 3% to about 15% Al2O3, up to about 20% BaO, up to about 15% B2O3, up to about 10% K2O, up to about 10% Na2O, up to about 10% ZrO2, up to about 5% MgO and up to about 5% PbO and less than 0.5% ZnO. Glaze compositions comprising the zinc-free glass frits can be fired using conventional double fast firing, single fast firing, and gres porcellanato ceramic firing cycles.