4.1 Put the weighed dore in the porcelain crucible and pour a few volume of dilute nitric acid (1;4) and place it on the hot-plate; heat (but not to boiling) until vapor can be seen rising from it.4.2 A dissolving the Ag, decant the solution without pouring off any Au.4.3 Then add a few volume of a stronger solution of nitric acid (1;), place it again on the hot [plate and heat (but not to boiling) vapor arises. Note; at the stage Ag is totally dissolve.4.4 Decant the solution without pouring off any Au.4.5 Apply the stream of hot-distilled water from the wash bottle tangentially to the sides of the crucible.4.6 Decant off the last drops of water and let it dry on a warm plate.4.7 Anneal the gold by heating it on a Bunsen burner or to an annealing furnace in order to expose its true color.4.8 Weigh the gold.4.9 Finally compute for the weight of Au (gm/Mt) and Weight of Ag (gm/Mt)