The circulation of commodities is the original precondition of the circulation of money.
There is a physical relation between physical things. But it is different with commodities.
Money appears as measure (in Homer, e.g. oxen) earlier than as medium of exchange, because in barter each commodity is still its own medium of exchange. But it cannot be its own or its own standard of comparison.
We cannot tell by looking at the diamond that it is a commodity. When it serves as a use-value, asthetic or mechanical, on the breast of a harlot, or in the hand of a glasscutter, it is a diamond and not a commodity.
The labour-power is a commodity , not capital, in the hands of the labourer, and it constitutes for him a revenue so long as he can continuously repeat its sale; it functions as capital after its sale, in the hands of the capitalist, during the process of production itself.
The values of commodities are directly as the times of labor employed in their production, and are inversely as the productive powers of the labor employed.
Gold is now money with reference to all other commodities only because it was previously, with reference to them, a simple commodity.
Money degrades all the gods of man and converts them into commodities.