
This five-hole crucible plug, made with high-grade C-50 graphite, fits into the grain-making crucible and regulates the flow of molten metal to optimize grain size and uniformity. 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.