Since carbon deposits form natural flake graphite when they are under pressure and temperature, graphite is most commonly found in metamorphic rocks, and the deposits are fairly evenly distributed throughout the rock. There are large flake graphite, medium flakes, and fine flakes.
Depending on the application, the purity and/or size of natural crystalline flake graphite may be more important. The spherical industry requires large-size and flake graphite, while the refractory industry mainly focuses on the flake size.
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