A Google Earth view of the White Plain Salt Works (Click on the image for a larger view)Our next scheduled ride is on April 14th to the White Plains area and a visit to the Desert Crystal Salt Works. Another salt works in the area is the Eagle Salt Works discovered and developed by Benjamin Franklin Leete, starting in 1870. Recognize the name Leete? It's where Leeteville Junction (Carson City cutoff) gets its name.
So I started to ask myself (and Larry), why did they mine so much salt? Well, the answer lies in all the silver that was being mined in Virginia City and the surrounding area. It just so happens that salt was used in the process of removing the silver from ore.
According to the book "Mines of Churchill and Mineral Counties" by William O. Vanderburg, the White Plains salt deposit was a notable source of salt production in Nevada. It was discovered by Walter Schmidt in 1870, and shortly after it was acquired by the Desert Crystal Salt Co., which operated for many years. The salt was produced by solar evaporation in a series of vats dug in the surface of the Humboldt Sink. The vats comprised a total length of 8,500 feet and were 55 feet in width. The brine was pumped into the vats from salt springs in the vicinity. Beginning in 1911, the International Salt Co., operating under lease from the Desert Crystal Salt Co., produced small amounts of salt annually for several years; the last production of record was in 1915. Although the bulk of the salt obtained here was used in the reduction of silver ores in the early days, some salt was also refined for domestic and dairy purposes.
It was stated elsewhere in the book that one acre of vats would produce 10 tons of salt daily during good weather! Wow, that's a lot of salt! Desert Crystal Salt Works had 467,500 square feet (8,500 x 55) of surface area, which is 10.73 acres (1 acre = 43,560 square feet). So on a good day, those vats could produce 107 tons of salt.
After the cyanide process gained favor in the 1890s, the Pan Process was forgotten, and so was the need for all that salt which led to the demise of both salt works.
Below is an explanation of the various processes used to refine silver from ore, and the part salt plays in it:
From Wikipedia, the free encyclopedia
Pan Amalgamation Process
The Pan amalgamation process is a method to extract silver from ore, using mercury. The process was widely used from 1609 through the 19th century; it is no longer used.
The patio process had been used to extract silver from ore since its invention in 1557. One drawback of the patio process was the long treatment time, usually weeks. Alvaro Alonso Barba invented the faster pan process (in Spanish the cazo or fondo process) in 1609 in Potosí, Bolivia, in which ore was mixed with salt and mercury (and sometimes copper(II) sulfate) and heated in shallow copper vessels. The treatment time was reduced to 10 to 20 hours. Whether patio or pan amalgamation was used at a particular location often depended on climate (warmer conditions speeded the patio process) and the availability and cost of fuel to heat the pans.
The amount of salt and copper(II) sulfate varied from one-quarter to ten pounds of one or the other, or both, per ton of ore treated. The loss of mercury in amalgamation processes was generally one to two times the weight of silver recovered.
Washoe Process
The Washoe process, a variation of pan amalgamation, was developed in the 1860s by Almarin Paul and others, to work the ore from the Comstock Lode in Nevada, United States (Washoe was an early name for the area; see Washoe Valley). In the Washoe process, the copper pans were replaced by iron tanks with mechanical agitators. Each tank ("pan") was circular, and commonly held 1,200 to 1,500 pounds of ore that had been crushed to sand size. Water was added to make a pulp, and 60 to 70 pounds of mercury, along with one-half to three pounds each of salt (sodium chloride) and bluestone (copper(II) sulfate) were also added. A circular iron plate called a muller was mounted on a vertical shaft and lowered into the pan, and was rotated to provide both agitation and additional grinding. Heat was delivered to the pans by steam pipes. The iron filings worn from the muller and pan proved to be an essential ingredient in the process.
Reese River Process
A variation of the Washoe process was developed in the Reese River mining district around Austin, Nevada. The Washoe process was found not to work well for ores with arsenic or antimony sulfides, or with galena or sphalerite. In 1869, Carl A. Stetefeldt of Reno found that roasting the ore with salt converted the silver sulfides to silver chlorides, which could then be recovered in amalgamation pans. The process was introduced in the Reese River District in 1879, with great success.
~Dave
Update on Thursday, April 5, 2012 at 10:11PM by
Dave Faulk
I just added a Google Earth image of the White Plains Salt Works. Click on it for a larger image. You will be able to see the vats and layout, this 100 years after they were created!
~Dave
;)
