The EM-Tec RXS-18RE reference standard includes 18 reference rare earth elements and a 200µm aperture copper Faraday cup. All mounted in a Ø25.4 x 9mm high stainless steel 303 block. Intended as reference standard for quantitative EDS and WDS micro-analysis applications.Reference materials: LaF3, Ceo2, Pr, Nd, Sm, EuF3, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc, Y, U and C. 200µm copper Faraday cup. Sensitive to air, must be stored under vacuum or inert gas.