You have to dig your way deep into American history -- stretching back even prior to California's statehood -- to find the origins of Cliffs Natural Resources (NYSE: CLF). In 2010, Cliffs celebrated another landmark of longevity, marking 50 years since the company first listed on the New York Stock Exchange.

And what a golden anniversary this turned out to be! Cliffs crushed all-time company records by virtually every imaginable metric, and placed the Midas touch on a doubling of its sales revenue to carry net earnings across the $1 billion threshold. Those earnings scaled vertically by 360% to reach $7.49 per share.

Even after the stock's strong move above the century-mark in after-hours trading Wednesday, Cliffs' trailing P/E still clocks in at a reasonable ratio beneath 13.4. Fools are reminded to consider that valuation analysis of mining companies like Cliffs must give adequate consideration to the untapped value of mineral reserves, which generally yields higher ratios than investors are accustomed to seeing from other equity sectors. After a surprising nosedive in shares of Teck Resources (NYSE: TCK) last week, for example, that copper and met coal giant still carries a P/E ratio above 21. With Cliffs' earnings set to rise further in 2011 on meaningful strength in iron ore prices, this bargain-loving Fool finds exciting value baked into Cliffs' shares.

Cliffs continues to fire on nearly all cylinders. The company's North American iron ore unit delivered a 48% production boost on the heels of strategic acquisitions that pre-date the pending addition of Consolidated Thompson. Although the unit's costs tracked higher in 2010, average realized iron ore prices of $102.95 per ton permitted an incredible 111% surge in operating margin to reach $35.19 per ton. Iron ore operations in the Asia-Pacific region fared even better, with a doubling of per-ton revenues multiplying margins more than sixfold over the comparable 2009 margin. As output from Cliffs' latest acquisition carries production higher still in 2011, I see additional margin expansion bolstering the prospect for further advances in the company's shares. Particularly in the Pacific seaborne trade, where iron-ore behemoths BHP Billiton (NYSE: BH) and Rio Tinto (NYSE: RIO) look to expand production substantially, Cliffs' expectation of average 2011 prices above $175 per ton signal a period of incredible profitability for iron ore miners.

The one cylinder in Cliffs' growth engine that continues to misfire badly is coal. Back in October, I decried the unit's third-quarter production costs as "unacceptably high", which I suppose would render the huge sequential spike to $122.33 per ton for the fourth quarter something of a catastrophe. For all the operational challenges encountered by eastern met coal producers like Alpha Natural Resources (NYSE: ANR) and Patriot Coal (NYSE: PCX), these atrocious results earn this Fool's crown for the least attractive coal operations in 2010. Cliffs' gave away more than $25 for each ton of coal mined in the fourth quarters, as "adverse geological conditions" continued to plague two mines. Fortunately, coal now accounts for less than 10% of consolidated annual revenue, and the company's 2011 outlook calls for a prompt return to a positive operating margin.

Despite that bituminous fiasco, Cliffs deserves ample recognition for a truly remarkable overall performance in 2010, and warrants the careful attention of Fools looking to identify those momentum stocks with all the necessary fuel to keep their engines running. I am adding Cliffs Natural Resources to my watchlist, and invite you to join me by clicking here.