These three companies did not live up to Mr. Market's expectations last week.

We'll check them out a bit, because sometimes an earnings stumble is a signal to sell, but digging in the dirt is also a good way to find turnaround candidates while they seem stuck in the mud.

Don't take gold too literally
We're starting way down in an Indonesian gold mine. Freeport-McMoRan Copper & Gold (NYSE: FCX) reported earnings of $1.36 per share, some 19% below Wall Street estimates of $1.68. The miss happened mainly because of the volatility of copper prices and the structure of industry pricing contracts.

McMoRan is developing new properties in the Americas and the Republic of Congo, and sees much higher copper and molybdenum output in the upcoming year. With growing infrastructure needs in countries like China, India, and Brazil, those utilitarian metals should see continued price increases for years to come, while gold happens to be in vogue right now but faces a less certain future.

With those factors in mind, I'd much rather invest in proactive mining experts like McMoRan or Rio Tinto (NYSE: RTP) than in the shiny bricks themselves. Even an admittedly innovative gold bug like Goldcorp (NYSE: GG) relies too heavily on its precious, but not-too-useful, eponym for my tastes, and the diversified miners are trading at severe discounts to their highs from last fall. There's gold in them thar hills, in a figurative sense.

Home on the range
So we're out of the mine with our canary still a-twitter, and there's decent cell phone reception here in the open air. Communications specialist Qualcomm (Nasdaq: QCOM) was supposed to deliver pro forma earnings around $0.53 per share, but came up just short with $0.52 -- although revenue did beat the consensus estimate by 10%. That was good enough to send the shares up by 10.4% between two closing bells.

That magnitude of an earnings miss can happen because the CEO coughs during an awkward silence at a business meeting, or because a mid-level sales rep decides to part his hair on the left one day. In other words, it's tantamount to a rounding error and nothing to worry about.

The company does face challenges in the legal arena from tough competitors like Texas Instruments (NYSE: TXN), but I think fellow Fool Dave Mock said it best when he summed up Qualcomm as "resilient." It's the kind of company that inspires you to wait around for a significant price drop, because you just know that it will pull through in the end. And I don't think this week qualifies as a buy-in opportunity -- the stock is on the rise right now, as well as over the past year. Hold yer horses, mate.

I'll take my chocolate shaken, not stirred
Have a chocolate bar, cowboy. Candy connoisseur Hershey (NYSE: HSY) reached for an earnings bar set at $0.55 per share but fell a penny short. Management blamed the underperformance on unseasonably high prices on ingredients like milk, but noted that the pricing environment is falling back to normal levels. The company forecast 4% higher sales next year -- and then raised its wholesale prices by 3% a couple of days later. I guess that's one way to ensure that you meet estimates.

This is a deeply disturbed business right now, having ousted and replaced eight of 11 board members last November, after the controlling Hershey Trust lost faith in the steering committee. A rumored merger with overseas rival Cadbury Schweppes (NYSE: CSG) might shake things up again before the year is out, and it's very hard to tell right now where the company will be in a year or two.

So I'd grab some candy and sit down to watch the show until we've got a better view of Hershey's direction. As far as the stock has fallen recently, there might be even better deals ahead.

Foolish finale
Some of these underperformers are victims of larger circumstances; others might have only themselves to blame. It's up to you to decide which down-on-their-luck companies will pull themselves up by the bootstraps, and which are languishing in the muck for real.

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