All of a sudden the world's metals markets are making it appear that many of us should slink off into the corner and sit quietly, topped by high-pointed dunce caps. The latest evidence of the appropriateness of that approach has come from London-based mining giant Rio Tinto (NYSE:RTP).

After months of assuming that China's voracious appetite for minerals would likely be endless -- even amid sputtering economies of the OECD (developed nations) -- Rio Tinto has raised a cautionary flag, indicating that Chinese commodities demands are slowing. According to Rio's CEO Tom Albanese, who is in the midst of attempting to fend off a buyout incursion from Melbourne-based BHP Billiton (NYSE:BHP), the Chinese slowdown involves the nation's economy "pausing for a breath," but that its longer run vibrancy likely will be reignited by industrialization and urbanization.

However, the breath-taking also has played a major role in other ways. For instance, copper prices have been cut nearly in half just since July, resulting in a  precipitous 75% slide in the share price of Freeport-McMoRan (NYSE:FCX). Further, given the global economic softness, Rio Tinto will delay planned asset sales, which had been intended as debt-reduction measures following its nearly $40 billion purchase of Canadian aluminum producer Alcan last year.

And if all that weren't enough, a 12% joint stake in Rio Tinto taken down earlier this year by Aluminum Corp. of China (NYSE:ACH) -- Chinalco -- and Alcoa (NYSE:AA) appears to be frozen in Hong Kong as an offshoot to the liquidation of Lehman Brothers. The shares had been acquired in an effort to thwart BHP's intended purchase of its British rival.

So in short order, the mining sector has been transmogrified from the envy of global industry to appearing to be the work of Alice in Wonderland creator Lewis Carroll.

Nevertheless, for those Fools well steeped in patience, there likely have been some compelling longer-term values created in the group -- almost overnight.

My salient overall takeaway here is that, while Freeport-McMoRan -- and copper itself -- could slide for a while longer, a year to 18 months could yield significant profits in one of the world's largest publicly held copper, molybdenum, and gold producers. It's a prospect well worth Foolish attention.  

Despite its slide, Freeport-McMoRan continues to be accorded five stars to Motley Fool CAPS players. Does that rating include your vote?

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