Anthracite Coal
Picture Gallery of Sedimentary Rocks
The highest grade of coal, anthracite is a hard, shiny rock that is almost pure carbon. With more metamorphism it recrystallizes to graphite.
Photo courtesy Kai Hendry of Flickr.com, through Creative Commons license
See More About:
Related Articles
©2012 About.com. All rights reserved.
A part of The New York Times Company.