The GB/T 23513.4-2009 standard specifies the method for the determination of fluorine content in germanium concentrate. This part is analyzed by Ion selective electrode method, which is suitable for the determination of fluorine content in the range of 0.01% to 1.0%. The test sample is first melted with sodiumhydrate, and then most of the metal ions are extracted and separated by water. Subsequently, in a sodium citrate buffer solution with a pH of about 6.5, the fluorine Ion selective electrode is used to measure the potential difference, and then the fluorine concentration is determined. This method uses excellent grade pure reagents and requires precise configuration of the fluorine standard solution to ensure the accuracy of the determination.