Smith, Ricardo, Marx and Sraffa made no theoretical distinction between exhaustible resources and lands. The very notion of exhaustibility, however, can be opposed to that of `indestructible powers of the soil' (Ricardo) and calls for a specific analysis distinct from that of rent. The diversity of the contemporary attempts to deal with that question in a classical framework shows how varied are the understandings of the main methodological features of classical theory. Three crucial points emerge: first, the treatment of prices, which are invariant in classical theory but, according to the Hotelling rule, are changing through time for exhaustible resources; second, the notion and the measure of the rate of profits; and, third, the relationship between economic analysis and a more historical and sociological approach stressing the balances of power between classes. Our own approach starts from a very simple model, called the corn-guano model, where guano is the exhaustible resource, and examines the dynamics of such an economy on the physical side and the value side. These lessons serve as a basis for an extension to multisector models. We provide a critical assessment of a few alternative approaches developed by Sraffian scholars.