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> (1) carbon graphite chunks iso formed machinable
(1) carbon graphite chunks iso formed machinable
This is the only description i have found so be aware its not the best: These are all iso formed, dense and hard carbon graphite. Extruded or sintered is composed of larger grain graphite particles. These are perfect for crucibles, machining for molds or casting. Glass blowers use the sheets for placing hot glass on them to avoid cracking or hairline fractures. Machinists use these for making master molds or parts for molding.
I believe the technical term is "carborundum". Please view pics below:
