CONSOL Energy has decided to temporarily idle two coal mines, the Buchanan Mine in southwest Virginia and the Amonate Mining Complex in southern West Virginia.This doesn't stand out as particularly surprising news--after all, demand for coal is dropping, and factors like low natural gas prices, an unseasonably warm winter and upcoming environmental regulations have made it a tough year for the industry.But these two CONSOL mines are metallurgical coal mines. Metallurgical coal is the higher-grade, hotter-burning coal that's used to make steel, and the market has remained relatively strong as countries like India and China continue to develop and need steel. For many analysts, metallurgical coal and the demand for steel is going to be the major force in keeping the Appalachian coal industry (at least partially) alive for decades into the future.But as trade publication Coal Age reports, the demand is even dropping for met coal.