Important: Safety Warning
This page describes trade processes that use dangerously toxic materials such as cyanide solutions, mercury amalgams, or strong acids. These processes require training, equipment, and precautions far beyond what the text describes.
This information has been left in for historical purposes but should not be acted upon.
Carat Baths
The plating baths of a large establishment are made up to have the same alloy in them as is intended to be used in the anode, that is, 18k, 16k, 14k, etc., by adding cyanide of copper and cyanide of silver, or chloride of silver, to the gold bath above described. Or it may be made by battery, as described above, and any article intended to receive a certain quality of plate is put into its appropriate bath, weighed from time to time, and when it has received the allotted number of pennyweights, is given to the finishers.