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Gold parting
Gold parting is the separating of gold from silver. Gold and silver are often extracted from the same ores and are chemically similar and therefore hard to separate. Over the centuries special means of separation have been invented.
The very earliest precious metals had mixes of gold and silver; gold and silver alloy is called electrum. With the advent of coinage, methods had to be invented to remove impurities from the gold so that gold of specific purities could be made. Cupellation was able to remove gold and silver from mixtures containing lead and other metals, but silver could not be removed. Gold parting as a process was specifically invented to remove the silver. The main ancient process of gold parting was by salt cementation and there is archaeological evidence of that process from the 6th century BC in Sardis, Lydia. In the post-medieval period parting using antimony, sulphates and mineral acids was also used. In the modern period chlorination using the Miller process, and electrolysis using the Wohlwill process are the most widely used methods of refining gold by removing silver and platinum.
==History==
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