
Made from C-50 graphite and drilled with nine standard 0.025" (0.635mm) holes, these patented replacement discs fit AutoValve™ crucibles for the GrainPro™. Holes help ensure uniform grain size. C-50 graphite, created using isostatic pressure, a process that makes the material significantly more dense and therefore less absorptive, is ideal for working with white gold and high-karat yellow gold (18-karat and higher). The denser graphite stands up better against their solvent characteristics to deliver a longer service life when used with these metals.