A transparent polycrystalline yttrium aluminum garnet (YAG) ceramic is described wherein the ceramic is colorless and transparent in both as-sintered and post-sinter, air-fired states which makes it highly desirable for lamp applications. The transparent YAG ceramic is co-doped with an amount of MgO and an amount of ZrO2 wherein the weight ratio of MgO to ZrO2 is from about 1.5:1 to 3:1.
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