Cupellation is a process where ores or alloyed metals are treated under high temperatures and controlled operations to separate noble metals, like gold and silver, from base metals like led, copper, zinc, and others present in the ore or alloyed metal. The process is based on the principle that precious metals do not oxidize or react chemically, like the base metals; so when they are heated at high temperatures, the precious metals remain apart and the others react forming slags or other compounds. This process has been in use since the Bronze Age and still used today able to raise the gold and silver content to 95%, however the process cannot separate silver from gold, but this is good enough for me.
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