As silver continues to dazzle audiences worldwide with its seemingly tireless ascent, one can scarcely fault a Fool for getting a bit excited about the earnings that silver miners will soon begin to report.

With another 22.5% climb in silver prices recorded during the first quarter of 2011, quality silver miners are poised to enjoy still more of that epic margin expansion that has fueled the sector's truly epic outperformance of the market. Although Silver Wheaton (NYSE: SLW) already approached the pinnacle of corporate profitability in the fourth quarter of 2010 -- with an astonishing 82% net profit margin -- the company's unique, fixed-cost business model could yield a further 25% sequential expansion of its cash operating margin for the first quarter of 2011.

Fellow growth machine Endeavour Silver (NYSE: EXK) posted operating results for the first quarter this week, and reported a gorgeous average realized silver price of $33.18 for the period. Following a 20% production expansion that yielded 1.1 million silver equivalent ounces (SEOs) for the period, Endeavour remains on target to produce 4.7 million enormously profitable SEOs for the full year 2011. Endeavour expects full-year 2011 costs to trend just beneath its 2010 average cost of $5.71 per ounce, which translates to margin expansion that substantially resembles that of even Silver Wheaton.

Of course, the widest per-ounce profit margins in the industry will continue to belong to ultralow-cost sensations Hecla Mining (NYSE: HL) and Silvercorp Metals (NYSE: SVM). Sporting negative cash costs of production (after factoring in revenue from byproduct metals like gold, lead, and zinc), these miners are the cat's meow for margin-hungry investors.

But negative cash costs are certainly not required for a silver mining stock to yield phenomenal investment gains. A well-timed production growth spurt, combined with exciting potential for continued exploration success, is capable of propelling a silver stock with even greater force. In the case of my favorite silver miner -- Great Panther Silver (AMEX: GPL) -- issued guidance for 2011 production costs between $6.50 and $8 per ounce is not likely to interrupt a growth trajectory that has seen the shares quadruple in value over the past year. Moreover, with major producer Pan American Silver (Nasdaq: PAAS) forecasting 2011 cash costs between $7 and $7.50 per ounce, Great Panther's cost structure remains an impressive achievement given that its production scale is about 10% that of Pan American.

With silver prices now spending a significant portion of the second quarter above $40 per ounce -- and a number of factors suggesting continued strength on the horizon -- the difference of a couple of bucks between miners' operating cost structures seems scarcely perceptible. Fools with exposure to silver miners are bound to enjoy another spectacular set of earnings results for the first quarter of 2011, and it would require a massive reversal to prevent the second quarter from looking better still.

If the never-boring silver mining industry piques your Foolish curiosity, be sure to add these stocks to your free, personalized watchlist and follow all the precious news to come.