The mining boom and the river - Sierra Vista Herald

Cochise County is dotted with remnants of the mining booms of the late 1800s and early 1900s.  The San Pedro Riparian National Conservation Area is home to a number of these sites.  

When mining commenced in Tombstone, miners were faced with a dilemma. It was essential that ore be processed as close to the mines as possible to reduce transportation costs, but processing required water which was not available at Tombstone.  The solution was to build the mills that processed the ore along the San Pedro River, which is about 10 miles east of Tombstone. Water was moved to the mills by building dams upstream along the river, where it was diverted into sluices that led overland to the mills.   

Between 1878 and 1881, there were six major mills built along the river.  These were called stamping mills or sometimes reduction mills.  Their purpose was to reduce the total volume of the silver ore down to a product that could be transported more cheaply to a smelter for final processing.  Most of the mills conducted custom milling for numerous mines.

All of the San Pedro River mills were built on hillsides on the east side of the river.  Why on a hill?  Ore was hauled to the uphill side of the structures, where it was loaded into hoppers that fed the mill. Gravity assisted the processing as ore moved downhill and through the mill’s mechanical processes.  

Most notable were the “stamps” for which the stamping mills were named.  These were large metal rods, mechanized hammers basically, that pulverized the ore.  Accounts from the era describe the cacophonous scene as the mills crushed ore around the clock.

Water was essential to the operation.  It was heated to generate the steam that drove the stamps and other machines.  Water was also mixed with the pulverized ore as it was reduced.

The following is a list of the mill towns that sprang up along the San Pedro.  For each, we provide the mill name(s) located at that town, the number of stamps, and the associated mines.

· Two mills were located north of Fairbank at Contention City.  The Contention Mill had 25 stamps and processed ore from the Contention, Sulphurete and Flora Morrison Mines.  Also located here was the Sunset Mill, 10 stamps, which supported the Head Center Mine.

· One mile north of Fairbank was the Grand Central Mill, which had 30 stamps.  This mill processed ore from the Grand Central, Emerald, Silver Thread and State of Maine.

· South of Fairbank, Emery City housed workers of the Boston Mill, 20 stamps.  This mill supported the Vizina, Knoxville, Stonewall, Oregon, and Old Guard Mines.

· Millville was located where Charleston Road now crosses the San Pedro River.  Located here was the Gird Mill, 15 stamps, which processed ore from the Goodenough and Toughnut Mines.  Also at Millville was the Corbin Mill with 15 stamps, which processed ore from the Lucky Cuss Mine.  The town of Charleston across the river from Millville provided housing and amusement for the mill workers.

The mines in Tombstone started to penetrate the water table (approximately 520 to 620 feet deep) in late 1881. Pumps were brought in to keep the mines clear.  A side benefit was that the water pumped from the mines was now available for other use.  This allowed the movement of most milling activity from the San Pedro River to Tombstone, saving on transportation costs.

A small smelter was also set-up in Hereford to process ore from Bisbee’s Neptune Mine. It processed ore for only one year, 1881-1882. It closed and later was accidently burned.

By the early 1890s, the silver mills along the San Pedro River were closed and dismantled. The small towns associated with these mills eventually were abandoned and today, with the exception of Fairbank, all that remains are the foundations, which are large stone structures that are still impressive.

To learn more about mining and its technology, readers are directed to the Bisbee Mining and Historical Museum, which has excellent informational displays.  In addition the Arizona Historical Society Museum in Tucson has a stamping mill as part of the exhibit.

Another place to learn more is at one of the Friends of the San Pedro River history walks.  At 1:00 PM on December 10th, we will provide a tour of the Fairbank Historic Town-site.  At 1:00 PM on December 17th, another Friends walk will be held at Millville. Each tour entails a short hike. Wear a hat, sunscreen and walking shoes.  Bring water.   See our website for more information.