Nanoporous gold made by dealloying exemplifies how the exciting mechanical properties of nanoscale objects can be exploited in designing materials from which macroscopic things can be formed. The homogeneous microstructure and the possibility of adjusting the ligament size

L

between few and few hundred nm

along with the high deformability and reproducible mechanical behavior predestine the material for model studies of small-scale plasticity using reliable macroscopic testing schemes on mm- or cm-size samples. Such experiments tend to agree with the Gibson-Ashby scaling relation for strength versus solid fraction

while suggesting an essentially scaling of the local strength of the ligaments. By contrast

the elastic compliance is dramatically enhanced compared to the Gibson-Ashby relation for the stiffness. Contrary to intuition

the anomalously compliant behavior of the nanomaterial goes along with a trend for more stiffness at smaller

L

. This article discusses surface excess elasticity

nonlinear elastic behavior and specifically shear instability of the bulk

network connectivity

and the surface chemistry as relevant issues which deserve further study.