Open-cell and closed-cell solid foams are two idealized ends of a spectrum of solid porous materials. In the former, the empty space forms an interconnected continuous network intertwined with the structural one. In the latter, the gas intermixed with the structure forms distinct, unconnected cells, completely separated from each other by the structure’s elements. However, many protocols used to prepare porous metal materials result in structures intermediate in terms of properties between the two categories. Technical specifications quantifying the type of the porous material are typically based on measuring the proportion of empty space available to penetration by an invading gas (the so-called gas displacement method). We are proposing the usage of concepts defined in topology to quantify the properties of the intermediate porous metallic structures and to define an alternative- a precise ”cell-openness score” measuring how close a given structure is to an ideal open cell foam. We explore the usefulness of the proposed score on the toy example of structures based on Voronoi tesselations of space around point clouds. We also verify to what extent our ”cell-openness score” is useful in predicting z-direction Young’s modulus in a class of random porous structures.