There are various clues for the origin and meaning of the German word ‘saigern’. In Medieval foundries, it was first used to mean ‘turn into liquid’. The English term ‘liquation’ refers to the separation by smelting of lead containing silver from a copper/lead alloy. The process utilises the different melting points of the individual metals and their temperature-dependent miscibility.
The liquators had to make sure the temperature was right so that only the lead containing silver (process lead) flowed off the top and the liquation ‘cakes’ did not melt completely. What were known as liquation thorns were formed in the channels of the liquation furnace. These fragments of copper contained very little lead and silver.