- usually produced and/or sold by many different companies
- Is uniform in quality between companies that produce/sell it. You cannot tell the difference between one firm's product and another.
In textbook examples commodities are usually sold for their marginal cost of production, though in the real world the price is often higher, due to factors such as barriers to entry and firm specific talents (perhaps one firm is more adept at growing oranges than another).
Commodity ResourcesExchange Rates and Commodity Prices
Commodities and Other Futures