The GB/T 16477.2-2010 standard specifies the determination method of calcium, mg and manganese content in rare earth ferrosilicon alloys and mg ferrosilicon alloys. The method is suitable for samples with calcium content ranging from 0.50% to 6.00%, mg content ranging from 0.20% to 11.00%, and manganese content ranging from 0.50% to 4.00%. After the sample is analyzed by nitric acid and hydrofluoric acid, it is further treated with perchloric acid, and finally in dilute muriatic acid medium, excited by argon plasma Light source, the elemental content is determined by Light spectrum method. The standard details the required reagents and materials, including the preparation method of standard solution, to ensure the accuracy and Reliability of the determination results.