Koke ya peteroli ya Graphite (GPC) Ibisobanuro:FC: 99 % min S: 0.05max Ivu: 0.5 % max VM: 0.5% max Ubushuhe: 0.5% max Ingano: 0.5-3mm; 1-5mm, 3-8mm, 8-30mm, 0-30mm Gupakira: Amasakoshi Manini (Dukurikije ibyo abakiriya bakeneye, dushobora gutanga ibisobanuro bitandukanye n'ingano.)