We recall the basic geometric properties of the projective variety Latn r (K) parametrizing a family of special lattices over Witt vectors proved in [Hab05, HS, San04]. They are ’Schubert varieties’ in the analog of the affine Grassmannian for G = SL(n) over a complete local field of mixed characteristic, and are normal and Gorenstein [HS]. In this paper, we prove that there exists a set of sub...