Known under various names including crystalline vein, Plumbago, Sri Lankan graphite, and Ceylon graphite, “Sri Lankan” and “Ceylon” are commonly used for vein graphite since the island nation of Sri Lanka (formally Ceylon) is the only area to produce this material in commercial quantities. Serious mining and exportation of Ceylon graphite began about 1824; however, the unusual deposits of Ceylon have been known, and apparently used locally, since the middle of the 1600s.
Vein graphite is a true vein mineral, as opposed to a seam mineral (amorphous graphite) or a mineral that is disseminated throughout the ore rock (as in flake graphite). All currently available commercial vein graphite is mined in Sri Lanka.