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).
After about 10 minutes, you will see the coals starting to glow through the vents and flames starting to flicker over the top layer of coals. Pour them out into a pile and wait until the coals are mostly covered in ash and gray in color. Then spread the coals out. The entire process takes approximately 15 minutes.