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Precious Metal Prices

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Refining Molds
Use rectangular ingot molds for refining of precious and base metals. Pouring molds can be used in a cascading arrangement for larger pours producing multiple bars. Conical slag molds can be used at the bottom of a cascade to collect the slag, or for producing conical metal buttons.
Assay Molds
Assay molds are used for pouring fire assay fusions. This separates the slag from the lead button. Typically, the small conical lead button will be pounded square for easier handling and to remove and slag that sticks to the button.
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).