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Pouring Bullion Molds

All cast iron molds: Minor surface defects and a semi smooth surface are common with sand or no-bake foundry processing. Porosity is superficial and should not affect the life of the mold in any way. Typically, customers will coat the inside surface with a refractory material to avoid burn in and premature pitting. Also, it is recommended to heat the mold before pouring to avoid thermal shock which will break the mold in half. In addition, a release agent such as a graphite spray is recommended to reduce sticking.  The melting point of our heat resistand cast iron is 1300-1450C (2350-2600oF).