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Ｃａ氟碳钡铱矿富Ｓｒ变种和白云鄂博矿富Ｃａ变种分别产于俄罗斯科拉半岛希宾碱性岩体的碳酸盐和内蒙古白云鄂博钥铁稀土矿床碳酸盐脉石中。据电子探针分析得到的晶体化学式分别为：（Ｃ３＿（０．４６），Ｎａ＿（０．２８），□＿（０．１６））＿（０．９０）Ｂａ＿（１．０３）（Ｃｅ＿（０．８２），Ｓｒ＿（０．３８），Ｌａ＿（０．３５），Ｎｄ＿（０．３２），Ｐｒ＿（０．０９），Ｓｍ＿（０．０１））＿（１．９７）（ＣＯ＿３）＿４Ｆ和（Ｎａ＿（０．４４），Ｃａ＿（０．３２），□＿（０．２４））＿（１．００）Ｂａ＿（１．０７）（Ｃｅ＿（１．０３），Ｌａ＿（０．４６），Ｎｄ＿（０．２６），Ｐｒ＿（０．０８），Ｓｒ＿（０．０８），Ｓｍ＿（０．０２））＿（１．９３）（ＣＯ＿３）＿４Ｆ。由Ｘ射线方法测定的晶胞参数分别是：ａ＝０．５０９１，ｃ＝２．３０２ｎｍ和ａ＝０．５１１０，ｃ＝０．３３３ｎｍ。二者是Ｃａ氟碳钡铈矿（Ｃａ＿（０．５），□＿（０．５））ＢａＣｅ＿２（ＣＯ＿３）＿４Ｆ和白云鄂博矿ＮａＢａＣｅ＿２（ＣＯ＿３）＿４Ｆ类质同象系列的中间成员。基于白云鄂博矿晶体结构中离子半径的分析和键价的计算，表明Ｃａ＿￣（２＋）优先占据Ｎａ位，而Ｓ?
The Ca-rich barium-iridium-rich Sr-rich varieties and the Bayan-Obo-rich Ca-rich varieties are respectively produced in the carbonate rocks of the Hibin alkaline rock mass in the Kola Peninsula, Russia, and carbonate gangue in the Baiyunebo iron-key rare earth deposit in Inner Mongolia. According to the electron probe analysis, the crystal formulas are as follows: (C3_ (0.46), Na_ (0.28), __ (0.16)) _ (0.90) Ba_ (1.03) 0.82, Sr 0.38, La 0.35, Nd 0.32, Pr 0.09, Sm 0.01 0.01) (1.97) (CO 3) 4F (0.44), Ca_ (0.32), __ (0.24)) _ (1.00) Ba_ (1.07) (Ce_ (1.03), La_ (0.46) , Nd_ (0.26), Pr_ (0.08), Sr_ (0.08), Sm_ (0.02)) _ (1.93) (CO_3) _4F. The unit cell parameters determined by the X-ray method are: a = 0.5091, c = 2.302 nm and a = 0.5110, c = 0.333 nm. Both of them are intermediate members of the CaB (0.5), □ (0.5) BaCe_2 (CO_3) _4F and NaBaCe_2 (CO_3) _4F isomorphic series of Bayan Obo. Based on the analysis of the ion radius in the crystal structure of Bayan Obo and the calculation of the bond prices, it is shown that Ca 2+ takes the priority of Na atom,