Parkes process

chemistry

Also known as: Parkes zinc-desilvering process

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June 17, 2026

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The Parkes process is a method used in chemistry to extract silver from lead. Developed by Alexander Parkes, it involves adding zinc to molten lead. The zinc then reacts with any silver and gold present, forming compounds that are lighter than lead. These compounds rise to the surface, forming a crust that can be skimmed off, thus separating the precious metals from the lead. This process was patented in 1850 and is a significant contribution to metallurgy.12

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Alexander Parkes
This procedure, commonly called the Parkes process (patented in 1850), involves adding zinc to lead and melting the two together. When stirred, the molten zinc reacts and forms compounds with any silver and gold present in the lead. These zinc compounds are lighter than the lead and, on cooling, form…
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This procedure, commonly called the Parkes process (patented in 1850), involves adding zinc to lead and melting the two together. When stirred, the molten zinc reacts and forms compounds with any silver and gold present in the lead. These zinc compounds are lighter than the lead and, on cooling, form…
Read More

silver processing
From lead concentrates
Silver is removed by the Parkes process, which consists of adding zinc to the molten lead bullion. Zinc reacts rapidly and completely with gold and silver, forming very insoluble compounds that float to the top of the bullion. These are skimmed off and their zinc content recovered by vacuum retorting.…
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Silver is removed by the Parkes process, which consists of adding zinc to the molten lead bullion. Zinc reacts rapidly and completely with gold and silver, forming very insoluble compounds that float to the top of the bullion. These are skimmed off and their zinc content recovered by vacuum retorting.…
Read More

lead processing
Refining of bullion
The Parkes zinc-desilvering process is the most widely used pyrometallurgical method of refining lead bullion. As in smelting, the lead is first melted and again allowed to cool below the freezing point of copper, which crystallizes and, along with any remaining nickel, cobalt, and zinc, is…
Read More
The Parkes zinc-desilvering process is the most widely used pyrometallurgical method of refining lead bullion. As in smelting, the lead is first melted and again allowed to cool below the freezing point of copper, which crystallizes and, along with any remaining nickel, cobalt, and zinc, is…
Read More