The world's largest publicly owned copper company is, as you might expect, not thriving amid the sharp slide in the price of copper and other commodities. On Tuesday, Freeport-McMoRan (NYSE:FCX) announced that its income for the third quarter had dropped substantially, as copper prices have fallen by about half since early July.

Specifically, net income for the quarter was $523 million, or $1.31 a share, compared with $775 million, or $1.87 a share, for the same quarter of 2007. Revenue slipped to $4.62 billion, from $5.07 billion a year ago.

The drop in most commodities prices around the world hasn't been kind to Freeport shareholders, just as it has taken its toll on other giant miners, including BHP Billiton (NYSE:BHP), Rio Tinto (NYSE:RTP), Vale (NYSE:RIO), and Alcoa (NYSE:AA). In Freeport's case, the company's shares have fallen about 70% from mid-May to Monday's close at $36.72.

Nevertheless, while prices for copper have fallen, volumes have remained steady. For instance, copper prices approached $4.00 a pound on the COMEX market for metals futures in July; now they're close to $2.00. Nevertheless, Freeport sold 1 billion pounds of the metal in the most recent quarter, up from 949 million pounds in the third quarter of 2007. But because the average realized price was $3.14 a pound in the third quarter, we can look for further deterioration in the average price realization in the current quarter.

At the same time, the company's gold and molybdenum volumes increased in the quarter. And unlike their slipping copper cousins, gold price realizations increased by 25%, while molybdenum's price per pound climbed by 15%.

It wasn't long ago that copper prices and demand were at such high levels that what my aunt refers to as no-goodniks were making off with air conditioning tubing and telephone cables, simply for the resale values. It's a different world now, and it's clearly impossible to predict the severity or length of global copper price declines.

However, with Freeport's forward P/E trading at just about 4.2 times -- a number that's subject to some adjustment as the most recent quarterly results are digested -- my inclination is to watch this quality company carefully, but to forgo building or adding a position until commodity prices have definitively resumed moving north.

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