Reeling from renewed concerns over European debt contagion -- and the notion that there may in fact be Earthly limits to China's explosive growth rates -- the recent resurgence of uncertainty within equity markets had already bludgeoned many promising commodity stocks before this patriot was thrown to the slaughter on Tuesday.

Indeed, I had recently added Patriot Coal (NYSE: PCX) to my silverminer CAPS portfolio precisely because I considered the shares disproportionately battered by the sudden mood shift on Wall Street. From their 52-week high notched in late April, Patriot shares had already tumbled some 36% when I made my CAPS pick earlier this month. The Market Vectors Coal ETF (NYSE: KOL), as a rough sectorwide reference point, had lost only 24%. Notwithstanding the increased regulatory scrutiny confronting Appalachian coal miners on the wake of Massey Energy's (NYSE: MEE) tragic mine explosion, I considered Patriot an unmistakable investment opportunity beneath $16 per share.

Because I view the broader picture for pan-Asian coal demand as a multi-decade, structural shift in global market dynamics that even a slowdown in China's growth would be unlikely to derail, I likewise view the coal sector's sell-off as fundamentally unwarranted. I intend to hold my top coal picks Peabody Energy (NYSE: BTU) and CONSOL Energy (NYSE: CNX) for the very long haul.

Into this boiling cauldron of coal-sector weakness, Patriot dropped the untimely announcement that it will permanently close its Harris No. 1 mine in the company's Rocklick mining complex. Following a roof collapse over the conveyor system on June 12, Patriot decided to close the mine due to "sudden adverse geological conditions."

We have seen from the BP fiasco the horrendous consequences of ignoring safety concerns in the blind quest for profit. While the market penalizes Patriot Coal, I commend the company for recognizing that some profits are not worth chasing. Patriot shed more than 16% of its market capitalization Tuesday, and this, in my view, yielded one of the most oversold equities I have witnessed in 2010.

The Harris No. 1 mine has indeed been an important component of Patriot's high-margin metallurgical coal production. In 2009, the mine produced 11.5% of the company's total met coal volume of 5.4 million tons. Although met coal fetches a significantly higher price than thermal coal, the mine's 2009 contribution to Patriot's consolidated coal production volume amounted to less than 2%. What's more, since Harris No. 1 was on its last legs and was slated for closure in 2011, the mine did not factor significantly into Patriot's plan to expand annual met coal production by two-thirds -- to 9 million tons -- within two years. Although the lost production may force a slight delay in reaching that goal, I see no reason to interpret this setback as a material hit to the growth initiative.

Perhaps recognizing a severely overblown reaction, investors have bestowed a 5% consolation prize onto Patriot's shares ... but I consider Patriot Coal a seriously compelling opportunity anywhere below my CAPS-pick entry price near $15.50.

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Fool contributor Christopher Barker can be found blogging actively and acting Foolishly in the CAPS community under the user name TMFSinchiruna. He tweets. He owns shares of CONSOL Energy, Market Vectors Coal ETF, and Peabody Energy. The Motley Fool scrubs its disclosure policy before releasing it into the atmosphere.