Barrick Gold Corp. (NYSE: ABX) and Agnico-Eagle Mines Ltd. (NYSE: AEM) both release earnings Wednesday. Besides cranking out gold, that's about all these two companies have in common. Taken together, they're a study in contrasts; the yin and yang of gold miners.

That's made manifest in the companies' ability to surprise analysts. We postulated the surprise potential for these two companies in our recent earnings preview ("Will Gold Stock Earnings Surprise Anyone?"). Based upon Barrick's recent tendency to outperform expectations and Agnico-Eagle's propensity to lag analysts' estimates, we adjusted the then-current consensus earnings figures upward for Barrick and downward for Agnico-Eagle.

Last week, the Street thought Barrick would deliver 36 cents a share in first-quarter earnings. Our model says 37 cents is more likely. Analysts pegged Agnico-Eagle's EPS at 10 cents; we're looking for 9 cents.

So, why does one company gladden our hearts and the other disappoint? It's all in the numbers, really.

Barrick Gold Corp.

Barrick's moniker as a gold corporation is well-earned. By far, its revenue exposure is heavily skewed toward the yellow metal. Fully 84% of fiscal 2008 revenues came from gold sales; the remaining 16% is attributed to copper.

Sales, at $7.91 billion, rose 25% year over year. The rise was accompanied by a nearly equal uptick in costs. Well, nearly equal percentagewise. In actual dollars, the company increased top-line income by $849 million.

Big offsets lurked further below the line, though. Like a whopping $707 million jump in impairment charges. After filtering out these charges, the company's income from continuing operations fell 2% to $1.45 billion.

Fiscal 2008 saw Barrick's average cash cost for gold leap nearly $100 an ounce to $443.

Gold production is heaviest in North America, amounting to 40% of the company's output.