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螢石經常进行分析的有氟化鈣、碳酸鈣、二氧化硅、硫等項目。氧化铁、氧化鋁、氧化鋇、鋅、鉛等項目不常分析。而氧化鎂、氧化鈦、五氧化二磷、氧化鉀、氧化鈉及氧化錳等項目只在全分析时才进行測定。二氧化硅的測定一般采用重量法,試样須用氢氟酸处理2～4次,这样需要較长的时間。氟化钙采用草酸沉淀鈣,以高錳酸鉀容量法或重量法測定,由于經过沉淀、过滤、洗涤等操作,手續也此較繁多。利用EDTA滴定鈣、鎂是簡捷准确的方法,在螢石中测定鈣,則需要用硫酸进行冒烟处理去氟,然后进行滴定,这是因为在碱性溶液中鈣与氟成为沉淀影响結果,而氟化銨在EDTA滴定鋅、鎘、錳等元素时,是作为鈣、鎂、鋁的掩蔽剂的。EDTA亦曾用于氟化钙的分析中,但只是作为草酸沉淀鈣时掩蔽其他元素之用。螢石中硫的測定,过去使用的是大家熟知的硫酸鋇重量法。
Fluorite regular analysis of calcium fluoride, calcium carbonate, silica, sulfur and other projects. Iron oxide, alumina, barium oxide, zinc, lead and other projects are not often analyzed. The items such as magnesia, titanium oxide, phosphorus pentoxide, potassium oxide, sodium oxide and manganese oxide were only measured at the time of full analysis. Determination of silica commonly used gravimetric method, the sample must be treated with hydrofluoric acid 2 to 4 times, which takes a long time. Calcium fluoride precipitated calcium oxalate to potassium permanganate capacity method or gravimetric method, due to precipitation, filtration, washing and other operations, the procedure is also more numerous. The use of EDTA titration of calcium and magnesium is a simple and accurate method for the determination of calcium in fluorite, which requires the use of sulfuric acid for smoke treatment to fluoride and then titration because of the precipitation of calcium and fluorine in alkaline solutions, The ammonium fluoride in EDTA titration of zinc, cadmium, manganese and other elements, as calcium, magnesium, aluminum masking agent. EDTA has also been used in the analysis of calcium fluoride, but it is only used as a masking element for oxalate precipitation. Determination of sulfur in fluorite, the past is the well-known barium sulfate gravimetric method.