Suitable for: Jewelry industry, Bank, Pawn industry，Gold and Precious Metal research lab. Only two weighing steps, the purity% of precious metals and gold karat can be showed rapidly and accurately. 2. No stains and scratches left on gold after testing, it doesn't need to use the sulfuric acid solution to test the standard samples. 3. With the special software design, it can directly and circularly show the gold karat (including gold-copper-silver, gold-silver, gold-copper), gold purity%(including gold-copper-silver, gold-silver, gold-copper) 4. With the function of HI and LO limit, the wide karat range from 9K to 24K and the data of HI and LO can be set freely. 5. With the mixture proportion function, it can test other precious metals, such as: platinum, silver, palladium, copper, rhodium?and so on 6. Can't test the samples inlaid precious stones and hollow samples. It can be used as general balance.