Lewis H. Parrish and R. M. Roberts, have secured a patent in England for improvements in the separation and extraction of copper from its ores. The object sought is the chemical treatment of copper ores, so as to obtain a greater per centage of pure copper from the ore, and also to render available refuse ore. The ore, if large, is broken up into lumps of about two or three inches cube. These are then placed in a furnace, calcined, and kept at a dull red heat. After being sufficiently roasted, the ore is withdrawn from the kiln through a trap underneath, and instantly passed through two pairs of ordinary crushers, the first pair of which will reduce it into small lumps, and the second will pulverize it. While still hot it is next plunged into an acid bath made of lead or slabs of slate, to stand heat. This tank is placed inside an iron tank containing water, and fire is applied to the bottom of the water tank ; the solution is to be kept within a few degrees of boiling point. The ore muBt be kept frequently stirred. When the solution has taken up all the copper, it should be drawn off through a filter into a second tank, containing iron to precipitate the copper. The tank is to be kept warm by a low heat under the bottom. When the whole of the copper has been precipitated, the solution may be carefully drawn off into another vessel, and is then ready to be rinsed after adding fresh acid. The precipitate left in the tank is then thoroughly cleansed with water, laid upon a drying stove, thoroughly dried, and is then ready for melting.
This article was originally published with the title "Extraction of Copper from Ore"