By beginning with a small amount The reverberatory furnace commonly used for cupelling goes by the name of the English cupelling furnace.
The latest cupelling furnaces have the general form of a reverberatory copper-smelting furnace.
The intervening kettles contain leads with silver contents ranging from above market to below cupelling lead.
Of zinc, all the gold and copper and some silver and lead will be alloyed with the zinc to a so-called gold - or copper - crust, and the residual lead saturated with zinc. By removing from the surface of the lead this first crust and working it up separately (liquating, retorting and cupelling), dore silver is obtained.