If you take into account the tremendous changes in the world's commodities and economic situation during the past year, there was more than a little to be optimistic about in Freeport-McMoRan's (NYSE:FCX) earnings report released Tuesday.

For the quarter, the company managed earnings of $812 million, or $1.38 a share. Last year, it checked in with net earnings of $1.28 billion, or $2.25 a share. The company's revenue also slid to $3.68 billion, from the $5.44 billion it posted a year ago. So while Southern Copper (NYSE:PCU) managed a 68% year-over-year decline in earnings, Freeport-McMoRan held its downside to 37%.

Though prices for copper and molybdenum both remained well below what they were in last year's comparable quarter, when copper had just returned to less than $4.00 a pound, the red metal nevertheless has recovered from a slide of about $1.40 at the beginning of this year to about $2.50 a pound now. Freeport-McMoRan averaged $2.22 per pound for copper during the latest quarter.

At the same time, the company's quarterly copper production increased to nearly 1.1 billion pounds, from 942 million pounds for the second quarter of 2008. The increase from a year ago reflects Freeport-McMoRan's mining of a higher-grade section of its huge Grasberg open-pit mine in Indonesia, balanced against cuts in output in North America.

Freeport-McMoRan operates copper mines in North America, South America, Indonesia, and Africa. Its Tenke Fungurume mine in the Democratic Republic of Congo is still in its startup stage. The company is also the world's largest molybdenum producer, operating primarily from its Henderson underground mine in Colorado.

According to the company's conference call, underlying demand for both copper and molybdenum appears to still be coming from China, resulting in the steady upward price movement during the first half of 2009.

While I'm convinced that many of the mining stocks -- Rio Tinto (NYSE:RTP), BHP Billiton (NYSE:BHP), and Vale (NYSE:VALE) certainly included -- bear watching, I'm hard-pressed to name a company that has pulled itself together more quickly than Freeport-McMoRan. On that basis alone, I'd suggest that my Foolish friends keep a very close eye on what I believe to be an unusually promising opportunity.

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