A coke Cupellation furnace still in use at the Mint is shown in front and side elevation in Figs. 95 and 96. It consists of an
The Gold Fire Assay Process of ores is almost universally conducted in the dry procedure by furnace methods. Exceptions will be noted later. The plan
The difficulty of roasting arsenical and antimonial ores may be avoided by taking ore, 1 A.T. ; red lead, 1,000 grains; sodium carbonate, 500 grains;
The following remarks on the use of the fire assay fluxes and litharge may serve as an aid in arriving to a correct composition of
Calculating gold from your fire assay ends with reading the equipment called the gold scale or “the balance”. This equipment should turn with 1/200 milligramme
The object of the Fire Assay Fusion is to concentrate the precious metals in a button of lead, while the whole of the remainder of the
Start following 911Metallurgy’s Linkedin page to get a free (my used) hardcopy of: The History of Grinding by Lynch & Rowland I will select a
The bead of silver and gold obtained by cupellation is squeezed between pliers, or flattened by a hammer on a clean anvil, to loosen the
Listed and explained in details below are 8 Gold Assay Methods which are alternatives to the classic fire assay method. Amalgamation Assay This is useful in
How to detect gold in loose alluvial ground has been already described. A similar method may be employed in the case of auriferous quartz after grinding