Precious metals
Kennecott Utah Copper produces about 400,000 troy ounces of gold per year, with a purity of 99.99%. The molten gold is poured into 400 troy ounce bars, which are then sold to customers.
We also produce about 4 million troy ounces of silver every year, with a purity of 99.9%. The bars we pour are larger than gold bars, weighing 1,000 troy ounces each.
Gold and silver in the Bingham Canyon Mine occur in minute quantities and are extracted as impurities in the final stage of refining the copper.
Gold - Minimum purity (fineness) of 9999's in 400 FTO bars
available at Brink's Vault, Salt Lake City, UT
Silver - Minimum purity (fineness) of 999's in 1,000 TO bars
available at Brink's Vault, Salt Lake City, UT
How Do We Produce Gold and Silver?
Here's what happens: After going through the concentrating, smelting operations and casting furnaces, the copper ends up in large, thick plates called copper anodes. These anodes are 99.6% pure copper. Not quite good enough for us, so we put them through one last process at the refinery. Here, the copper anodes are lowered into an acid solution just inches away from a cathode on each side. The cathode is just a large stainless steel sheet, the same size as the copper anode. We apply an electric current between the plates which causes the copper ions to migrate from the anode to the cathode. This forms plates of 99.9% pure copper, our final product.
Meanwhile, all the other impurities - including silver and gold particles - drop off into the solution and settle to the bottom. The residue from that solution goes to the precious metals plant, where we put it through a series of chemical processes to separate out the gold and silver. The last step in the production process is to stamp each bar with Kennecott's brand, the lot number, the weight, and the fineness of the metal - that is, the percentage of gold or silver in the bar. After that, we ship the bars to an armored car service's vaults. From there, we sell the gold and silver to our customers.
More information about our products are available by accessing the link below:
Gold Product Spec Sheet
Gold Environmental Profile
Silver Product Spec Sheet
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