Martin McGuinn, who took over as chief executive two years ago, is a lawyer by training and oblivious to banker's hours: He's gazing over Pittsburgh from his top-floor office by 5:30 every morning, when the three sprawling rivers below are still black as the coal buried deep in the surrounding hills.

FORBES: Pittsburgh Panther

While the US has turned to shale gas, Europeans have once again embraced the black stuff, as the cost of coal has plummeted.

BBC: Green energy on the back foot after carbon trading blow

Located next to the convention center, the stadium would have doubled the mass and length of the huge bunker against the river already established by that "lump of black coal" -- as essayist Phillip Lopate described its dark bulk in his literary trip around the edges of Manhattan -- cutting off views and access with nearly a mile of hulking wall.

WSJ: New York Stadium Deals: Good and Bad

Coal exporters are downcast, as they also face low global prices for the black stuff.

ECONOMIST: From a royalties bill, the strong rand and lawsuits