This paper studies Carl Menger's theory of the emergence of a commodity money. We propose an interpretation of Menger's learning by imitation process based on the search theoretical formal framework. We show that there exists a tension between the importance of intrinsic properties of commodities and the pure conventional self-fulfilling expectations of agents. This confirms the role of imitation in the emergence of monetary equilibria in search theory. We conclude that Menger's approach may support the idea that the fundamental property of a commodity-money (namely its great liquidity) is the result of its emergence process and not necessarily of its original intrinsic properties.