Development of Lead Foil Standard Samples for Fire Assay

The lead foil used in fire assay was developed by following GB/T 15000 series of standards and YS/T 409—1998 industry standard. The lead foil is 0.1-0.2 mm in thickness and 3 g in weight with a square shape. The lead foils were evaluated to measure Au and Ag concentrations by six laboratories with different experimental methods of fire assaying with ICP-AES and ICP-MS. Since the analysis data were tested by the Dixon test and Shapiro-Wilk test methods, the mimetic normal distribution data of Au and normal distribution data of Ag indicated that the lead foil is highly homogeneous and suitable to for obtaining accurate data for analysis. This lead foil has been approved as the industry standard material, due to the excellent results obtained.