Fire Assay Features

Fire assay is not only a method for enriching gold and silver in ancient times, but also an important method for analyzing gold and silver. Geology, mining and gold and silver smelting plants at home and abroad regard fire assay as a reliable analytical method and widely use it in production. Some countries have established fire assay as a standard method, and my country has also established it as a national standard method for the determination of gold in gold concentrate, copper concentrate, jewelry gold and composite gold. With the development of science and technology, there are more and more new technologies for analyzing gold and silver, and analytical instruments are becoming more and more advanced. Compared with other methods, the operation procedure of fire assay is longer and requires certain skills. Many analysts have tried to use other analytical methods to replace flame analysis. However, the fire assay method is irreplaceable. For the determination of gold content in high-content gold raw materials or pure gold, its precision and accuracy are not as good as other direct determination methods. In the arbitration analysis of gold and silver content, the fire assay method can provide convincing results to both parties in dispute. This flame analysis has many unique advantages that other analytical methods do not have.

(1) Sampling is representative. Gold and silver often exist unevenly in the sample at the level of <g/t. The fire assay method generally takes 20~40g of sample, and even up to 100g or more can be taken. Therefore, the sample is representative and the sampling error can be reduced to a lower limit.

(2) Wide adaptability. It can be applied to almost all sample ores, from gold concentrate to mixed gold. The fire assay method can accurately determine gold and silver, including stibnite, which cannot be solved by the current wet analysis. For the main component analysis of pure gold, the fire assay analysis can also obtain satisfactory results. This method is applicable to almost all types of minerals except for a few samples.

(3) High enrichment efficiency, reaching more than 10,000 times. A small amount of gold and silver can be quantitatively enriched into the test buckle from a few grams of sample containing a large amount of matrix elements. Even if micrograms of gold and silver are enriched, the loss is very small, generally only a few percent. Since the composition of the particles (or enriched slag) is simple, it is beneficial to use various test methods for determination in the future.

(4) The analysis results are reliable and accurate. Over the years, some scholars at home and abroad have tried to completely replace the fire assay method with new wet chemical analysis or instrumental analysis, but have failed so far.