Companies like Silver Wheaton rely on purchasing precious metal streams. It seems to make sense that, in addition to any precious metal or metal in general, a company could purchase streams for any commodity, especially commodities which are durable in nature.
Are there any companies like this?
For those who are not familiar with the concept, a precious metal stream is basically where a company gives a mine a certain amount of money and in return the mine agrees to sell that company a certain amount of the goods produced for a fixed price, often far below the regular selling price. I guess you could think of it as a hybrid between a loan and a long term purchase agreement.