Philip Argall's practical work to commercialize gold cyanidation changed the course of the gold industry. When introduced in the early 1890s, gold cyanidation aroused significant skepticism, not least on the part of Argall himself. However, in the summer of 1893, working as a consultant, Philip Argall went to a failing Deadwood, South Dakota, cyanide mill built in 1891-1892 and, with plant modifications, made it work. It was the first of its kind.
Next, Philip Argall took the Brodie Mill in the Cripple Creek District from “fiasco” to success. Within three years, this 30-ton-per-day mill was expanded to 400 tons per day, the largest in the Cripple Creek District.
In 1893, Philip Argall was proffered the job of designing from scratch and operating a new plant to process Cripple Creek ores at Cyanide, Colorado. Argall designed the 400-ton-per-day Metallic Extraction Company mill at Cyanide to include massive dryers and roasters, rows of roll crushers, and a cyanide vat structure the size of a football field. Argall started the cyanide process by roasting ores ahead of cyanidation. In this processing step, he soon was using multi-tubular roasters of his own design.
The plant at Cyanide was the world's first for direct treatment of sulfa-telluride ores. Mines throughout the West studied and copied it: at Congress, Arizona's biggest gold mine; at Delamar, Nevada's biggest gold camp; and at Mercur, Utah, where the size of the Golden Gate mill eclipsed Philip Argall's Cyanide mill by 1898.
In the spring of 1899, Philip Argall introduced the 8-hour work shift at the Metallic Extraction Company mill. Argall's mill was the first in Colorado to adopt the 8-hour shift. This work practice attracted a better class of worker, reduced turnover, and increased production per man hour. Later in his career, Philip Argall called the introduction of the 8-hour shift his greatest accomplishment. At the same time, Argall said, “It has been my privilege to see the cost of treating Cripple Creek ores by wet methods reduced from $15 per ton in 1893 to $3.50 per ton in 1898 and to $1.38 per ton in 1913.“
In 1905, the Zinc Commission of the Government of Canada hired Philip Argall to investigate the zinc resources of British Columbia and test the ores to determine the best commercial process for beneficiation. Ores from the great Sullivan deposit were among those tested. In 1906-1907, Philip Argall designed the Golden Cycle Mill at Colorado Springs, Colorado, which remained the world's largest dry roasting cyanide mill. In 1907, Philip Argall started an investigation of flotation that continued until his death.
Philip Argall was born at the Colig lead mine in County Down, Ireland. Prior to arriving in the United States in 1887, he worked at mines, mills and smelters in Ireland, Wales, Cornwall, New Zealand and Mexico.
The cyanide process Philip Argall perfected and made profitable remains the dominant process for gold extraction more than 100 years after it first attracted his attention.
