Intense solution and solid state phosphorescence was observed on a novel photostable gold (I)-sitver(I) cluster with hypercoordinated carbon, [Au6Ag2(C)(dppy)(6)](BF4)(4), which has a core structure of a hexagold(I) octahedron with two silver(I) atoms capping on a pair of its faces; the incorporation of silver atoms enhances the rigidity and integrity of the cluster.