We present results of a high statistics study (O(2000) configurations) of the
quark masses in the MS-bar scheme from Lattice QCD in the quenched
approximation at beta=6.0, beta=6.2 and beta=6.4 using both the Wilson and the
tree-level improved SW-Clover fermion action. We extract quark masses from the
meson spectroscopy and from the axial Ward Identity using non-perturbative
values of the renormalization constants. We compare the results obtained with
the two methods and we study the O(a) dependence of the quark masses for both
actions. Our best results are m_s^(MS-bar)(2 GeV)=(123 +- 4 +- 15) MeV and
m_c^(MS-bar)(2 GeV)=(1525 +- 40 +- 100) MeV.Comment: 3 pages, Talk presented at LATTICE97(QCD Spectrum and Quark Masses).
Small misprints corrected, no conclusions change
