The lowest price at which coals can be sold for any considerable time, is, like that of all other commodities, the price which is barely sufficient to replace, together with its ordinary profits, the stock which must be employed in bringing them to market. At a coal-mine for which the landlord can get no rent, but which he must either work himself or let it alone altogether, the price of coals must generally be nearly about this price.
Rent, even where coals afford one, has generally a smaller share in their price than in that of most other parts of the rude produce of land. The rent of an estate above ground, commonly amounts to what is supposed to be a third of the gross produce; and it is generally a rent certain and independent of the occasional variations in the crop. In coal-mines a fifth of the gross produce is a very great rent; a tenth the common rent, and it is seldom a rent certain, but depends upon the occasional variations in the produce. These are so great, that in a country where thirty years purchase is considered as a moderate price for the property for a landed estate, ten years purchase is regarded as a good price for that of a coal-mine.
The value of a coal-mine to the proprietor frequently depends as much upon its situation as upon its fertility. That of a metallic mine depends more upon its fertility, and less upon its situation. The coarse, and still more the precious metals, when separated from the ore, are so valuable that they can generally bear the expense of a very long land, and of the most distant sea carriage. Their market is not confined to the countries in the neighbourhood of the mine, but extends to the whole world. The copper of Japan makes an article of commerce in Europe; the iron of Spain in that of Chile and Peru. The silver of Peru finds its way, not only to Europe, but from Europe to China.