Nevada Magazine highlights the history of the Donovan Mill in “Shaping History at Donovan Mill” To read the full story, CLICK HERE.

A significant landmark of Comstock history

A significant landmark of Comstock history The Donovan Mill in Silver City is an internationally significant site, representing the location where cyanide/zinc processing was perfected in a way that set the stage for the subsequent 115+ years of precious metal mining throughout the world. Some historians claim that the original part of the Donovan Mill, the Dazet Mill, and the adjacent Jackson Cyanide Plant is the location on the Comstock where the cyanide process discovered in Scotland (1887) was revolutionized for processing ore. The use of cyanide and zinc for the retrieval of precious metals was conceived in Scotland in 1887. Limited testing in New Zealand and elsewhere proved the value of the process. In 1896, Professor Robert Jackson from the University of Nevada School of Mines adapted the idea and perfected the process, especially for Comstock ore. He conducted tests on Comstock mill tailings, and then at the turn of the century, he set up a more formal operation at the industrial complex now known as the Donovan Mill today and the Dazet Mill or Jackson Cyanide Plant. The success of his experiment opened the door for the industry to cease using mercury for processing gold and silver ore, arriving at an approach to milling that was more efficient and better for the environment.

F. S. Lacrouts built the Dazet Mill in 1890 funded by Dazet, with ten stamps crafted refurbished at the Virginia & Truckee Railroad Foundry in Carson City. When Jackson and his partner Dr. J. Warne Phillips outfitted the mill for cyanide processing, they added tanks and rooms to the south. Phillips eventually bought out Jackson and then sold the mill complex to William Donovan, Sr. in 1912. In 1938, his son William Donovan, Jr purchased twenty stamps from the Rock Point Mill (Nevada Mining, Reduction, and Power Company) in Dayton. He added these four 5-stamp batteries on the Donovan Family’s third expansion of the mill, which completed an impressive bank of thirty of these industrial pistons, designed to pound ore into powder. The mill processed ore until 1959.

Efforts to save Donovan Mill

The Comstock Foundation for History and Culture purchased the complex for $195,000 in 2014. The Foundation has spent funds, thus far, stabilizing the roof supports, which threatened to collapse. Each restoration project has a discrete price (estimates can be provided), but the entire complex will require approximately $4 million to bring it back into service entirely. Ultimately, the complex will serve as an interpretive center, and it could house various arts and crafts micro businesses associated with the historic period of the Comstock. You can help the Foundation transform this historic site into an accessible public gem on the Comstock.







A sense of urgency The Donovan Mill in Silver City is an internationally significant site, representing the location where cyanide/zinc processing was perfected. The Donovan Mill urgently needs support for restoration: the east wall is failing with high risk of losing the Dazet structure.  The main roof support beam in the mill is at the brink of failure and could cause the collapse of the roof structure. The roof is not watertight. Almost all windows are in need of repair, currently allowing the elements to intrude into the structure. The southwest corner of the structure and the zinc press room have been undermined and are about to fail; and flood debris is compromising the west wall of the structure. With all of that in mind, an amazing amount of the material dating to the turn of the century survives. Five of the thirty original stamps could be placed back into operation soon with little investment, and the structure could be stabilized and made safe for visitors to tour this location, which is pivotal in the history of industrial technology. PLEASE HELP SAVE DONOVAN MILL: CLICK HERE





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