Britannica Sources used in this answer

How is graphite obtained from natural deposits and petroleum coke?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

A labeled diagram of the periodic table entry for carbon, showing its atomic number 6, symbol C, electron configuration, atomic weight range, solid physical state, hexagonal crystal structure, and weakly acidic oxide properties. Color coding and icons indicate it is a nonmetal, solid at room temperature, with hexagonal structure and weak acidity. — carbon Carbon and its properties.

Graphite is obtained through both natural extraction and synthetic manufacturing processes.

Natural Deposits

Naturally occurring graphite is found in older crystalline rocks, such as gneiss, schist, and marble, as well as in coal and shale deposits. It is extracted using both surface- and deep-mining techniques. Once mined, the material undergoes flotation to separate and concentrate the graphite from the surrounding rock.12

Petroleum Coke

The majority of commercial graphite is produced synthetically using petroleum coke as the primary raw material. This process involves heating the coke—which consists of small, imperfect graphite crystals surrounded by organic compounds—in an electric furnace at extremely high temperatures. This method yields a high-purity product, typically ranging from 99 to 99.5 percent pure graphite.12