Amorphous carbon is the name used for carbon that does not have any structure. Some short-range order can be observed, but there is no long-range pattern of atomic positions. The coal industry divides coal up into various grades depending on the amount of carbon present in the sample compared to the amount of impurities. The highest grade, anthracite, is about 90% carbon and 10% other elements. Bituminous coal is about 75–90% carbon, and lignite is the name for coal that is around 55% carbon.it is the softest of all types...