Determination of cerium in silicate rocks by electrothermal atomization in a furnace lined with tantalum foil Application to 19 international geological reference materials.

A 40-fold increase in sensitivity obtained by using a tantalum foil lining in a pyrolytically-coated graphite furnace permitted determination of low ppm levels of cerium in most silicate rocks. A preliminary preconcentration by oxalate and hydroxide co-precipitations was used before determination by use of a Varian GTA-95 atomizer coupled with an AA-475 spectrometer. The results for 3 synthetic and 19 international reference materials, including 4 new Canadian iron-formation reference materials, showed good recovery and satisfactory agreement with other published values.