каменный уголь(also called soft coal the most abundant form of coal, intermediate in rank between subbituminous coal and anthracite according to the coal classification used in the United States and Canada. In Britain bituminous coal is commonly called "steam coal," and in Germany the term Steinkohle ("rock coal") is used. In the United States and Canada bituminous coal is divided into high-volatile, medium-volatile, and low-volatile bituminous groups. Britannica Alexander Demidov)
