%0 Journal Article %T Dualities between finitely separated structures %A WiesŁżaw KubiŁż %A Krzysztof PszczoŁża %J Mathematics %D 2012 %I arXiv %X We study dualities between classes of relational topological structures, given by Hom-functors. We show that there exists a 2-element structure with infinitely many relations, which reconstructs all other structures generated by a 2-element one. As an application, we find a natural duality for the class of normal convexity structures. As another application, we give short proofs for several known dualities for classes of structures generated by a fixed 2-element structure. %U http://arxiv.org/abs/1212.3758v1