  In this article we study the subgroup of the Picard group of Voevodsky's
category of geometric motives generated by the reduced motives of affine
quadrics. Our main tools here are the functors of Bachmann, but we also provide
an alternative method. We show that the group in question can be described in
terms of indecomposable direct summands in the motives of projective quadrics.
In particular, we describe all the relations among the reduced motives of
affine quadrics. We also extend the Criterion of motivic equivalence of
projective quadrics.
