Nodular celestite(Chrysanthemum stone)，a specific celestite cluster in the Qixia Formation (Middle Permian) of South China, formed in the early diagenesisIn a course deciphering its origin，33 samples were analyzed for strontium isotopeThese samples include nodular celestites from Liuyang，Hunan Province and Huangshi，Hubei Province，and include replacement calcites，host rock (micrites) and vein calcites from Liuyang (Hunan Province)，Yongfeng (Jiangxi Province)，Huangshi (Hubei Province) and Laibin (Guangxi Autonomous Region)The 87Sr/ 86Sr ratios determined from the celestites range from 0.706981 to 0.707525 with a mean value of 0.707215，coincide with those of seawater of the late Artinskian to Roadian stagesThe 87Sr/ 86Sr ratios from replacement calcite，host rock and vein calcite are richer than those of celestiteBecause the genesis of the replacement calcite and vein calcite is obviously later diagenetic，their relative riching of  87Sr isotopic characteristics must have originated from the overprint of later diagenesisAnalogously,the 87Sr/ 86Sr values of micrite also include contributions of late diagenesisBased on geological context on the evolution of the celestite cluster，it is proposed that the Qixia nodular celestite reflects the 87Sr/ 86Sr value of the Qixia seawater more reliably than Qixia micrites do, and that the differences of Sr isotopic values between celestites and micrites may be of significance in evaluations of Sr isotopic data from micrites