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碘化铋络离子或硫脲铋络离子比色法适用於微量的测定;对含量高的铋矿常采用氯化铋酰(BiOCl)、磷酸铋(BiPO_4)、草酸铋[Bi_2(C_2O_4)_3]等重量法或草酸盐容量法;这些方法需要进行很长的手续来分离干扰元素,尤其是对铅的分离更感麻烦。Fresenius法或Hampe法手续也都很繁冗。Schwarzenbach 氏首先提出以碘化钾为指示剂,用乙二胺四乙酸二钠(EDTA)标准溶液滴定。Cheng氏曾详细进行了一些试验,在pH为1.5～2.0的硝酸溶液中滴定,主要对常见的元素做了干扰试验。其後,Fritz 改用硫脲为指示剂,进行了较详细的研究,但他们都是在标准溶液的条件下进行试验,没有应用於矿
Bismuth iodide complex ion or thiourea bismuth complex ion colorimetric method is suitable for the determination of trace; bismuth chloride high content of bismuth chloride often used (BiOCl), bismuth phosphate (BiPO_4), bismuth oxalate [Bi_2 (C_2O_4) _3 ] And other gravimetric or oxalate capacity methods; these methods require lengthy procedures to separate interfering elements, especially the separation of lead. Fresenius method or Hampe method are also very cumbersome. Schwarzenbach’s first proposed potassium iodide as an indicator, with ethylenediaminetetraacetic acid (EDTA) standard solution titration. Cheng has carried out some experiments in detail, titrated in nitric acid solution at a pH of 1.5-2.0, and mainly conducted interference tests on common elements. Since then, Fritz switched to thiourea as an indicator and conducted a more detailed study, but they are all tested under standard conditions and are not used in mines