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To meet the rapid development of zircon U-Pb geochronology and Hf-O isotope geochemistry,it is imperative to develop well-characterized zircon reference materials for microbeam analysis.Here,zircon KV01 separated from the Kaap Valley pluton,South Africa is introduced as a potential Archean reference material for microbe,am U-Pb age and Hf-O isotope determination.SIMS and LA-ICP-MS U-Pb isotopic measurements gave grand mean 207Pb/206Pb ages of 3233± 16 Ma (2s,n=90)and 3230±26 Ma (2s,n=52),which are consistent with reported CA-ID-TIMS results.Slight heterogeneity of oxygen isotopes is revealed by SIMS analyses that yielded a relatively large δ18O range of 4.61-6.51‰.Among them,the zircon grains with clear oscillatory zones give a grand mean δ18O value of 6.17±0.33‰ (2s),which is suggested to record the primary O isotopic compositions.The homogeneity in the Hf isotopic compositions of KV01 zircon was checked by the laser ablation and solution MC-ICP-MS methods.They yielded consistent results with a recommended 176Hf/177Hf ratio of 0.280810±0.000013 (2s).The results reported here demonstrate that KV01 zircon could be a reliable reference material for microbeam 207Pb/206Pb age and Hf isotope determinations of ancient zircons,and be suitable as a quality monitor for SIMS oxygen isotopic analysis.