By induced fission track uranium mapping of a zircon crystal from the Kirchberg granite (Western Erzgebirge) different U concentrations in the core and an outer zone have been determined. The U concentrations in the core and the outer zone differ by a factor of 12. The estimated partition coefficient between zircon and a granitic groundmass amounts to K ≃ 1800. From these data the concentration of U in the progenitor of Western Erzgebirge, Older Granite Suite, was deduced to be 0.7 ppm.