Show compressed AIR AIK WITH CYANIDING by T 13 JOSEPH having read y your our valuable paper for several years and remembering its many contributions from various parties I 1 must say they are often very interesting as well as very beneficial I 1 might add the following suggestions which may help some weary mining man to obtain much better results than heretofore in the cyaniding cyan iding of ores I 1 will state that if the cyanide man used compressed air agitation and barium dioxide and some other elements with his fils cyanide solution in accordance with patents recently issued he would find that he could obtain better extractions with less cyanide consumption and in less time with less expense than heretofore was the general custom as by their use the iron particles and many of the otherwise injurious elements would not foul his solution nearly as much as they formerly did with the old methods when compressed air is conveyed upwardly with a slight inclination only and all through the ore as per patent issued lately it will not only convey the slimes to the top to aid percolation but it will also furnish plenty of oxygen and nitrogen to aid the metal solvent and also greatly neutralize the soluble iron and sulphur and other injurious substances in the ore it is tolerably well known that when compressed air is forced into a pulp of ferrous compounds in the alkaline solution that it converts the ferrous sulphides sulp hides into ferric sulphide and the ferrous hydrates into ferric hydrate and greatly aids the work of the metal solvent it is also well known that compressed air is very beneficial with a cyanide solution as it is a fact that cyanide has but very little action if any on metallic gold in the absence of free oxygen for un roasting sulphur ets I 1 will say it is well known to some that the extra oxygen in the solution from the compressed air and the barium dioxide causes the pyrites to become oxidized to sulphate of iron whereupon the normal oxide of barium left and the oxygen and nitrogen of the compressed air then decomposes the sulphate of iron forming sulphate of barium and oxide of iron b oth both of which are insoluble which action causes the gold to be set at liberty from its former compounds and causes a much better quicker and cheaper extraction from powdered raw sulphur ets also with the use of compressed air and some other elements with cyanide the small particles of iron in the ore cannot injure nor waste but a very small f fraction of the cyanide in comparison to old methods as n nearly early all of the injurious substances especially the fine iron is prevented from causing injury to the solution and when the ore is properly le ached the solution oftentimes will contain one third more available cyanide than heretofore even in the leaching deachin 9 the same kind of ore with the same amount of cyanide with the proper use of compressed al air r and some of the other elements with a cyanide solution the operator will always be enabled to extract the same amount of gold from his ore in less than one third of the time that the old leaching methods required and thereby not only greatly increase the capacity of his mill but also have greater time to further leach his ore even after he had already extracted the same percentage of his metal that was formerly accomplished by the old method the using of compressed air as referred to will not cost nearly so much as the former methods and yet it will accomplish much better work with cyanide in a different way than heretofore was the practice and it is also very beneficial in treating slimes which can easily be separated from the solution with the proper kind of a self cleaning centrifugal mill |