Coal samples courtesy Dr. Alex Glass and the Division of Earth and Ocean Sciences, Duke Nicholas School of the Environment

Item Description

Coal was the source of energy that powered steam engines that initiated the Industrial Revolution. Since the 1890s, coal mining has been a contentious social and political issue. Since the1970s, much attention has been paid to the environmental impacts of using coal, including landscape destruction from strip mines and mountaintop removal, water and air pollution, and global warming.

Coal fossil from Pittston, Pennsylvania (left)
Fossil derived from the Lepidodendron genus of primitive, vascular, tree-like plants that were an important part of the coal forest flora. They thrived in the Carboniferous Period about 300 to 360 million years ago. This specimen is a carbonized composite mould in black shale.

Anthracite coal from Pittsburgh, Pennsylvania (middle)
Anthracite is the highest grade of coal, having the highest density of energy per unit volume.

Calamites coal from Pittsburgh, Pennsylvania (right)
Calamites were tree-like horsetails to which the modern horsetails (genus Equisetum) are closely related. Calamites, however, were medium-sized trees, growing to heights of more than 30 meters.

Courtesy of Dr. Alex Glass, personal collection, and
Division of Earth and Ocean Sciences
Duke Nicholas School of the Environment