The polishing slurry includes by weight percent, 0.1 to 50 metal oxy-acid accelerator, 0.5 to 50 cerium oxide abrasive particles and balance water. The metal oxy-acid accelerator is formed with a metal selected from the group consisting of chromium, lanthanum and rare earth metals 59 to 71, manganese, molybdenum, niobium, osmium, rhenium, ruthenium, titanium, tungsten, vanadium, yttrium and zirconium.