While dollar investors have suffered the pain of watching the currency slide, their counterparts in commodities have reaped the benefits that a lower greenback can bring.

The prices of all sorts of commodities from crude oil to copper wire have risen sharply over the past year, and analysts say that buoyancy has come in part at the expense of the sinking dollar.

The story goes like this: Most commodities are priced in U.S. dollars. As the dollar depreciates, it takes more dollars to price a commodity at what the market believes it's worth. A weak dollar also makes commodities more attractive to foreign investors, who find they can buy more of a product for less.

To be sure, surging commodity prices have root causes beyond a weak dollar. Markets cramped by tight supplies and swelling demand -- particularly from developing nations such as China -- have seen sharp price increases in recent years. At the same time, the speculative money following those trends has ballooned, pushing prices even higher.

Those factors helped drive nickel prices to more than $40,000 in February from less than $15,000 per metric ton at the start of 2006. Zinc prices more than doubled last year. Recently, lead and tin have been tallying fresh records almost daily.

But those gains also coincided with the dollar's steep descent.

"Most of these markets have been so volcanic this year, and this (the falling dollar) is what I would call an 'and' factor," said Barclays Capital managing director Paul Horsnell. "It's one factor supporting demand a bit."

The amount of speculative money in the commodities markets also has its link to dollar weakness, if somewhat indirect. Low interest rates in this country have contributed to an increase in so-called cheap money, which has given hedge funds the ability to borrow large sums to go after higher-risk, speculative assets such as commodities, said Jon Nadler, an analyst with Kitco Bullion Dealers.

That's left many commodity markets with the mark of "Godzilla-size footprints of the funds stampeding in and out of what they expect to be the next big play," Nadler said.

Interest rates underpin currencies. Historically low interest rates in the U.S. have over the past year contrasted with rising interest rates in Europe -- and the currencies have mirrored that divergence.

The euro, marching higher since the start of last year, bought an all-time record $1.3843 on Friday. Some analysts expect the euro to hit $1.40 before the end of the quarter.

As it relates to commodities, consumers often feel the pain first on the highway and in the home, say analysts.

A $75 barrel of oil and a $3 gallon of gas have a certain amount of dollar depreciation priced into them, according to Axel Merk, president of Merk Hard Currency Fund. The same goes for copper and nickel and zinc, the metals used to coat steel. Consumers feel that price inflation in the costs of home improvement and construction.

"The price at the pump goes up as the dollar goes down," Merk said. "It's the one area where you see the pricing follow through fairly rapidly."

The dollar hasn't just fallen against stout currencies such as the euro and British pound. John Lonski, chief economist of Moody's Investor Service, points out that the dollar has lost ground against the currencies of emerging markets, as well. In a year, the dollar has tumbled 15 percent against the Brazilian real, dropped 13 percent against the Indian rupee and fallen 5 percent compared with the Chinese yuan.

That increases the attractiveness of commodities to funds priced in other currencies and helps to explain the run-up in commodity prices, Lonski said.