Signature™ Graphites & Carbons
The Signature™ family of graphites and carbon materials, in powder and granular form, includes amorphous graphite, crystalline flake and vein graphites, synthetic (artificial) graphite, along with calcined petroleum cokes. These materials are sourced from selected and qualified mines and sources from around the world. Signature™ graphites and carbons are chosen to perform in the most challenging and in the simplest applications. They offer consistency and quality at an economical price.
Amorphous Graphite
This variety of graphite is typically formed by the metamorphism of coal beds or carbon rich sediments in association with igneous activity. It is generally a soft, darker black colored graphite, less reflective than other varieties of natural crystalline graphite. Commonly found as “microcrystalline” particles, this variety of graphite has a lower graphitic carbon level when compared to other naturally occurring crystalline graphite varieties.
Fig. 01
SEM of Amorphous Graphite
Crystalline Flake Graphite
Typically formed as flat plate–like particles, this variety of graphite is disseminated throughout layers of metamorphic rock, either in isolated pockets or more broadly distributed throughout the parent rock matrix. Generally, very brilliant in color, the size and thickness of the individual flakes can vary depending on the ore deposit. Unlike other varieties of natural crystalline graphite, flake needs to be mechanically/chemically processed or “upgraded” to reach the necessary carbon levels for industrial applications.
Fig. 02
SEM of Crystalline Flake Graphite
Crystalline Vein Graphite
This variety of graphite is typically found in fractures or fissures associated with metamorphic and/or igneous formations, hypothesized as being deposited in the vapor, or fluid state. Generally, a soft, very brilliant variety of natural crystalline graphite, it exhibits one of the highest degrees of crystallinity and in some formations, the most pure form of the natural crystalline graphite found. Vein can range from finer, needle–like grain to a more coarse massive lump.
Fig. 03
SEM of Crystalline Vein Graphite
Synthetic Graphite
Synthetic Graphite, sometimes referred to as artificial graphite, is found in two forms: Primary Synthetic, and Secondary Synthetic. Primary Synthetic is produced through the high temperature treatment of specific coke precursors. Secondary Synthetic is the by-product of graphite electrode and part manufacturing. They have a dark gray to black, flat appearance. Manufactured from calcined cokes, and graphitized at temperatures approaching 3000°C, these materials offer high purity, excellent lubrication, and electrical conductivity.
FIG. 04
SEM of Synthetic Graphite
