  It is a fairly known fact that most of the algebras appearing in the theory
of rings of differential operators, quantized algebras of different kinds
(including many quantum groups), regular algebras in projective non-commutative
geometry, etc... come equipped with a natural gradation or filtration
controlled by some finite dimensional vector space(s), e.g. the degree one part
of filtration or gradation. In this note we relate the valuations of the
algebras considered to unramified sub-lattices in some vector space(s).
