In my experience, when the price of a commodity skyrockets all at once it's due to market manipulation. If it rises slowly it may be a supply and demand issue.

Coming to mind is the Enron manipulation of West Coast electrical power. The prices went through the roof all at once. The neocons said it was a free market, pure and simple, that supply couldn't keep up with demand and that's the way it goes.

We now know how false that was.

Some time ago the same thing happened with silver, when the Hunt brothers tried to corner the market.

And it's happening now, as speculation and a de facto monopoly manipulate the market to their advantage with the connivance of the US military.

Arf