How Gold is Refined

Added: 2026-05-25

[00:00:00]Have you ever wondered how a large refinery can take raw gold from the mines and remove the impurities turning it into something absolutely gorgeous, pure 24 karat gold. They call it primary refining. The old method utilized chlorine and these big machines to remove impurities, but these are being phased out. The new machines are called pyrometallurgical advanced melting units or PAM. They basically superheat the gold and you can see here is the crucible where they put the gold into.

[00:00:34]Then the machine will be enclosed. It will boil off the impurities and they can refine the gold to about 95 or 96% pure. Before the gold can go into secondary refining, it must be melted down and poured into this unique shape.

[00:00:51]It kind of looks like a gift tag, but the gold will become an anode as it is suspended in a highly concentrated hydrochloric acid and nitric acid mix, which is heated to about 140° Fahrenheit. And this is going to eat away the rest of the impurities and leave you with 99.99% gold. These are the cathodes or the sponge or the sheets of pure gold that collect at the bottom of those cells and this gold is now refined to 99.996% all the way up to 99.998% pure.