Contact graphs have emerged as an important tool in the study of translative packings of convex bodies. The contact number of a packing of translates of a convex body is the number of edges in the contact graph of the packing, while the Hadwiger number of a convex body is the maximum vertex degree over all such contact graphs. In this paper, we investigate the Hadwiger and contact numbers of totally separable packings of convex domains, which we refer to as the separable Hadwiger number and the separable contact number, respectively. We show that the separable Hadwiger number of any smooth convex domain is 4 and the maximum separable contact number of any packing of n translates of a smooth strictly convex domain is 2n − 2 √ n . Our proofs employ a characterization of total separability in terms of hemispherical caps on the boundary of a convex body, Auerbach bases of finite dimensional real normed spaces, angle measures in real normed planes, minimal perimeter polyominoes and an approximation of smooth o-symmetric strictly convex domains by, what we call, Auerbach domains.for every x ∈ R d . We denote the corresponding normed space by (R d , · K ). If K = B d , then we denote the norm · B d simply by · . Thus E d = (R d , · ). A d-dimensional convex body K is said to be smooth if at every point on the boundary bd K of K, the body K is supported by a unique hyperplane of E d and strictly convex if the boundary of K contains no nontrivial line segment. Given d-dimensional convex bodies K and L, their Minkowski sum (vector sum) is denoted by K + L and defined aswhich is a convex body in E d .The kissing number problem asks for the maximum number k(d) of non-overlapping translates of B d that can touch B d in E d . Clearly, k(2) = 6. However, the value of k(3) remained a mystery for several hundred years and caused a famous argument between Newton and Gregory in the 17th century. To date, the only *

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