Abstract Based on experimentation on solution of samples, the author presents a method for analysing trace gold. The procedure is like this: the gold in the sample is dissolved at room temperature in 7% thiourea -15-20% sulfuric acid -1% hydrogen peroxide and 2g fluoride, and is enriched by foamed plastic loaded by active carbon, which is then ashed; gold in ashed materials is dissolved in hydrochloric acid-hydrogen peroxide, and colorimetric analysis is subsequently performed with improved bead separation method. In this way, gold content in the range of 0.001-10g/t can be determined for a sample 10g in weight. The method is extremely simple, convenient and sensitive, and can be conducted at the encampment of a reconnaissance team with the efficiency of determining 50 samples per day. As this method can avoid horrible smell given off when aqua regia is used to dissolve a sample, its application will surely have broad prospects.
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