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Volatile matter (VM) of PC is around approximately 0.3%, and its ash content is around 0.3% at maximum, whereas in needle coke the ash content generally does not reach to approximately 0.1%. The real density (RD) depends on its application, and it is mostly in a range of 2.13–2.15 in needle coke and mostly in the vicinity of 2.00 in amorphous coke and is adjusted with the calcination temperature in production.

The content of elements in PC is varied with the calcination temperature in production but is generally given as follows. The carbon content is approximately 98% or more in amorphous coke and is further increased in needle coke in which the calcination temperature is higher. The hydrogen content is below approximately 0.5%. The sulfur content is around 0.3% and its value in needle coke is slightly smaller than that in petroleum coke. The nitrogen content is around 0.5–0.8%, and its value in needle coke is higher than that in petroleum coke, and nitrogen is assumed to be the causative agent for an irreversible expansion (puffing) generated in graphitization in the production process of a synthetic graphite electrode. In metal elements as an impurity, the content of V, Ni, and Ti is less in needle coke than that in petroleum coke (see the Chapter 6.1.2).

PC contains little metal impurities and is low in VM so that there is no report specified on the environmental impacts and risks (see Section 6.1.3.5).