BariteWorld Vein Graphite is a naturally occurring form of pyrolitic carbon (solid carbon deposited from a fluid phase). The morphology of vein graphite varies from flake-like for fine particles to needle or acicular for medium-sized particles to grains or lumps for very coarse particles. Sizes range from 1-150 cm " The material is available in a variety of sizes ranging from fine powder to 10 cm lumps. Vein graphite has the highest degree of crystalline structure of any conventional graphite material. Electrical applications make use of vein graphite. Many of the highest quality electrical motor brushes and other current carrying applications.