in ancient customs, a term used for the melting of gold or silver, either to refine them or to examine their value. The method of doing this is explained at large in the Black Book of the Exchequer, ascribed to Gervaise, in the chapter De Officio Militis Argentarui, being in those days of great use, on account of the various places and different manners in which the king's money was paid.

Arsura is also used for the loss or diminution of the metal in the trial. In this sense a pound was said to ardere denarios, to lose so many pennyweights.

Arsura is likewise used for the dust and sweepings of silversmiths, and others who work in silver melted down.