Stone coal is not only poor anthracite with low carbon and low heating value, but a kind of low-grage polymetallic coexisiting mineral. It is black or ash black, and is characterized by high-ash content, high-sulfur content, low heating value and great hardness.

　　The stone coal here is found in the Cambrian bottom stratum. It is transformed from organic remains, i.e., homonemeae. which are subject to paludification and coalification under the condition of hypoxia environment such as shallow sea, lagoons, bays, etc. It is ash black, containing a plenty of pyrite, quartz vein, phosphorite nodule, calcareous concretions. The calorific value of stone coal is not high, which is a fuel with low calorific value.

　　Stone coal with high calorific value can be used as the fuel of thermal power generation. Vanadium-containing stone coal can extract vanadium pentoxide. Since stone coal generally contains elements such as heavy metals that are harmful to the environment, which is not suitable as a civilian fuel or construction material.