This award, made through the Major Research Instrumentation (MRI) Program, provides partial support for the purchase of a Multicollector Inductively Coupled Plasma Mass Spectrometer (MC-ICP-MS), and associated hardware. The instrument will be housed in a new Plasma Analytical Facility (PAF) at the National High Magnetic Field Laboratory (NHMFL). We will use the instrument for: - mantle geochemistry to constrain the processes that result in mantle heterogeneity as the instrument allows improved analyses of Hf and Pb isotopes as well as in-situ trace element analyses; - cosmochemistry by measurement of heavy elemental abundances in extra terrestrial materials. returned from the GENESIS and STARDUST missions. For this project the MC-ICP-MS will be coupled with a single collector instrument for the determination of the major elements. - low temperature geochemistry where the MC-ICP-MS allows metal stable isotope analysis. Foremost will be Fe-isotope analyses to investigate the cycling of Fe in the oceans. The MC-ICP-MS will be instrumental in our development of a Biogeochemical Dynamics Program, an interdisciplinary program that will focus on the interplay between chemistry and biology in aquatic ecosystems and which will make use of the unique instrumentation at the NHMFL. We will develop the protocols to measure the isotopic composition of environmentally significant metals like Cu, Zn, Mo and Hg. At the NHMFL the instrument will also be of use to the material science and condensed matter physics faculty.