We conjecture that in the absence of new mixing effects at the weak scale the standard quark mass eigenstates and the quark weak eigenstates would coincide, and that for all three families a simple hierarchy would apply, with muo > mdo. We further assume that the observed mass inequality md > mu arises from mixing of d with a heavier quark D. This approach leads to a CKM matrix that is automatically expressed in terms of mass ratios and different from other ones that have been studied; it is consistent with experimental constraints. In addition to requiring the existence of D with a mass on the electroweak scale, in general an unambiguous prediction is that |Vtd| = |Vub|, which is soon testable. The approach can be implemented in E6-based models.Research supported in part by the US DOE and by CAICYT.Peer reviewed