The ability to measure trace element distributions on the microscale i
s often critical to our understanding of large scale geological proces
ses, As the number of different instruments and techniques capable of
trace element analysis increases the choice of analytical method is be
coming less clear. Although most techniques have 1 micrometre spatial
resolution as their ultimate goal It is clear that the analytical dept
h is determined by sample thickness (proton probe and synchrotron XRF)
or analytical volume (ion probe and laser ablation-ICP-MS) considerat
ions, Thus ability to produce brighter and smaller beams also requires
significant improvement in the detection of secondary particles. Prov
ided analytical considerations, such as precision or detectibility are
met, tile eventual choice between competing techniques may well be mo
re mundane aspects such as ease of access and cost.