About 2000 microprobe analyses of zircon were evaluated in order to characterize typical compositions of zircon from common and rare-metal granites of different geotectonic/geochemical affiliations. Generally, zircon is chemically variable at all scales of research. This detailed study shows that the contents of minor elements vary more widely than usually expected from individual analyses. While the Zr/Hf ratio is a reliable indicator of the degree of fractionation of the parent magma, all proposed indicators of the geotectonic position of the source magma, like Y contents or Y/Yb and U/Th values, were found to be merely indicative. Zircon from peraluminous (S-type) granites crystallizes early, is often enriched in P, Al, U, W, Nb and Bi, its (Y+REE)/P values are usually <<1, and the Zr/Hf values mostly evolved from 100 to 10. Zircon in A-type granites is often a relatively late mineral, mostly enriched in HREE and Th, having low Y/Yb and high (Y+REE)/P values, and its Zr/Hf values evolved from 100 to 5. Zircon in peralkaline rocks either crystallizes primarily or results from the transformation of older zirconosilicates. In both cases, it is rich in Y, poor in U and Th, displays high (Y+REE) / P values and Zr/Hf values >50. The effect of the geotectonic environment of crystallization is particularly evident in late, more evolved rocks, while zircons from the early and less fractionated rocks of all geochemical types are similar.