Mr. Obama rarely plays with other politicians - though he has played 7 times with Vice President Biden. In a fence-mending gesture, Mr. Obama invited then-House Speaker John Boehner to play on one occasion in June 2011 along with Gov. John Kasich, both Ohio Republicans.
Here are some ways to classify coal (by grouping it with similar types of rocks): Because slag formed from lava-like melted rock, it's sort of like an igneous rock -- but because humans made the melt, it's not a true igneous rock. So, we made up a new classification for slag: We call it a pseudo-igneous rock (pronounced SUE-doe ig-NEE-us).
Waste coals are the low-energy-value discards of the coal mining industry. Waste coal is called culm in the eastern Pennsylvania anthracite coal region and gob or boney in the bitiminous coal mining regions (western Pennsylvania, West Virginia and elsewhere).Waste coal piles accumulated mostly between 1900 and 1970. The piles look like hills or small mountains that are dark and barren.here are currently 18 waste coal burning power plants, and 13 more that use it as a secondary fuel, with bituminous coal as their primary fuel. Fourteen of the 18 waste coal plants are in Pennsylvania.