COBWEB CORNERS: Inner workings of a gold mill
By Mel McFarland
I have talked about the gold mills, but just what did they do? The large chlorination plant of the Standard Mining and Smelting company started in full operation in March 1900. It was located southwest of the corporate limits of Colorado City, on the lines of the Colorado Midland and the Colorado Springs and Cripple Creek District Railway, and could process from 600 to 700 tons of ore per day.
Immense storage bins were conveniently situated under the railroad tracks for receiving and storing shipments of ore. The first step in the milling process was the big rolling mills, which broke the rock into gravel. These chunks then traveled to a "bedding" floor, where they were mixed, sorted and prepared for treatment. Next in line was the dryer, where any moisture was removed. From the dryer, the ore was conveyed to the crushing department. This consisted of several sets of huge rollers, with screening and dust-collecting. The ore went from rock size to powdered sand, its grains as fine as sugar.
Belt conveyors took this sand to the roasting furnaces, each of which had a capacity of 100 tons per day. The ore was cooled automatically and moved to chlorination.
The chlorination department contained 11 chlorination barrels, each with a 10-ton capacity and the ability to handle from 35 to 40 tons per day. Chlorination was only one chemical tried on Cripple Creek ore. Later only cyanide was used. The other processes did not seem to obtain enough gold from the ore.
The precipitating building, so called, contained both the storage tanks and precipitating tanks. These vats received gold chloride solution from the chlorination barrels and were used for precipitating the gold from the solution. A filter process collected the precipitated gold sulfite. It was dried, roasted and further refined into nearly pure gold ingots and melted into brick form for shipment to the United States Mint at Denver.
The works were operated in connection with the Colorado-Philadelphia just to the north, which was owned by the same people and was Colorado City's first mill when it opened in 1896. The officers were Charles L. Tutt, president, Spencer Penrose, secretary and treasurer, Charles M. MacNeill, vice president and general manager.
Both mills closed in the teens, replaced by the bigger Golden Cycle Mill.