Sri Lankan Graphite is usually known as vein graphite or crystalline vein graphite. Sri Lankan graphite or Ceylon graphite is naturally occurring form of pyrolitic carbon (solid carbon deposited from a fluid phase). Vein graphite has a morphology that ranges from flake-like for fine particles, needle or acicular for medium sized particles, and grains or lumps for very coarse particles. An outstanding feature of vein graphite is that its deposits reach a graphitic carbon content of above 90%, even purities up to 99.5% are possible.

Vein graphite has the highest “degree of crystalline” perfection of all conventional graphite materials. As a result of its high degree of crystallinity, vein graphite is utilized extensively in “formed” graphite products that are used in electrical applications. Many of the highest quality electrical motor brushes and other current-carrying carbons are based on formulations using vein graphite. In friction applications, vein graphite is used in advanced brake and clutch applications. Commercial grades are available in purities ranging from 80-99% carbon, and sizes from 3-micrometer powder to 10-25 cm lumps.

There is a certain overlap in uses between natural and synthetic graphite that is controlled by price and purity.

Alternatively, natural graphite can be upgraded to the same specification through intensive thermal and chemical upgrading. China introduced low cost chemical purification methods for fine graphite in the ‘90s but these methods are not economical in Western countries. Since then, processing and purification has been improved and projects with high purity large flake graphite that require less purification have emerged. Natural graphite has another advantage in that it can be processed into other forms such as spherical and expanded graphite. Each of these forms changes graphite properties and makes it more adaptable to specific industry requirements. With these advancements, the overlap between synthetic and natural graphite applications is expected to grow.

An additional source of growth for graphite demand is the applications of graphene, a one atom thick layer of carbon atoms arranged in a honeycomb lattice that ultimately forms flakes of graphite when stacked together. Produced in laboratories for the first time about 10 years ago, the material is a hot topic for research in the scientific community and in the R&D labs of high-tech companies. Graphene has a unique set of properties that show potential to be used in a wide range of applications such as transistors, high sensitivity sensors, transparent conductive films for touch screen displays, more efficient solar cells and electrodes in energy storage devices. IBM has already fabricated a simple graphene based integrated circuit and Samsung has demonstrated a prototype flexible display, supposedly graphene based. Admitted, one of the main obstacles to all these applications becoming a reality is the lack of economically viable large scale graphene production. Several methods exist to produce both natural graphene (from flake graphite) and synthetic graphene, but all have certain limitations. Graphene production is still in its infancy and therefore it is hard to speculate which manufacturing method, whether natural or synthetic, will become the method of choice.

It is now fairly clear what potential graphite holds if all these new technologies are adopted over the next 10 years. The main question remaining is if the hunt for large flake deposits is justified or not? Do you really need large flake or can the cheaper fine and amorphous material do the same job? Discussions with manufacturers of graphite end products have highlighted one common theme – all flakes can be worked with, but the purification cost does not always allow it. As a rule of thumb, the larger the flake, the higher the purity of the concentrate and therefore less treatment is required to bring the graphite to above 97% C. This reduces production costs for the miner who can then sell it at prices normally achieved through chemical and thermal upgrading. The Chinese cost structure and lax environmental regulations have allowed this purification at low cost in the past, suppressing prices throughout the ‘90s. Recent changes in these regulations and increases in energy and transportation costs have driven the prices up to levels where high purity and thus larger flake deposits outside of China can once more be economical.