The paper reconsiders the nature of mining districts and property rights during the California
gold rush. According to a widely accepted view advanced by Umbeck (1977, 1981), in the
absence of effective legal authority, district codes established secure property rights in mining
claims. Drawing on a data set of mining district codes and a simple theoretical model, we argue
that the main historical features of mining districts may best be understood by viewing them not
as enforcers of private property rights, but as institutions for managing access to a nonrenewable
resource, in what was fundamentally an open-access context.