PRINCIPAL ELEMENT: 71.5%-73.0% MAXIMUM IMPURITIES%: Ca--0.020 Cu--0.005 Na--0.020 K--0.004 Cd--0.005 Fe--0.020 Pb--0.010 Mg--0.020 Ni--0.080 LASER DIFFRACTION: 1.0~10um REMAINS AFTER SIFT(STANDARD 100 MESH): ≤0.5% SPECIAL REQUIREMENT CAN BE NEGOTIATED BY BOTH SIDES