[en] ⁸⁷Rb-⁸⁷Sr analysis of the Norton County achondrite has been achieved with special attention to the rubidium analysis. Enstatite crystals and polycrystalline material give an 'age' of 4.48+-0.04x10⁹ years and an initial ratio ⁸⁷Sr/⁸⁶Srsub(I)=0.7005+-0.0004 (lambda=1.39x10^-11yr^-1, maximum errors). The feldspar component of the meteorite contains about 70% of the strontium and 30% of the rubidium of the whole sample, and does not lie on the isochron. Its model age relative to the strontium initial ratio of Allende is 4.6x10⁹ years. The data are consistent with a complex history dealing with an incomplete isotopic reequilibration of the meteorite, 120 m.y. after its formation at 4.6x10⁹ years, with an initial ratio similar to that of Allende. (Auth.)