Tintic Milling Company
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Knight-Christensen Metallurgical Co.
(1913 to 1915)
In 1912 Knight announced the erection of a new mill in Star Hollow, near Silver City. The mill was completed in the latter part of 1913 and utilized the Knight-Christensen process of chloridizing, roasting, and leaching, adapted primarily for treating low grade ores of the Knight mines, including the Iron Blossom, Colorado, Beck Tunnel, Black Jack, Dragon, and Swansea. The mill performed well during its experimental period, but on April 6, 1915, before certain mechanical problems could be corrected, a fire destroyed the plant for a complete loss of $150,000. (Eureka Reporter, September 5, 1912; September 20, 1912; October 18, 1912; February 19, 1915; April 9, 1915; Heikes History of Mining, page 117)
In the later part of 1913 a mill was completed at Silver City to use the Knight-Christensen process of chloridizing, roasting, and leaching, which was being adapted to treat the low-grade ores of the Knight mines, including the Iron Blossom, Colorado, Beck Tunnel, Black Jack, Dragon, and Swansea. The ores from these mines are said to afford an excellent variety of oxidized, sulphide, and siliceous material, from which to make a mixture most suitable to the process of treatment. (Geology And Ore Deposits Of The Tintic Mining District, Utah, USGS Professional Paper 107, 1919, page 117)
September 11, 1914
"The mill constructed last winter at Silver City has a capacity of 100 tons in twenty-four hours. This process was erected only for experimental purposes. It has gone through the tryout process incidental to the putting into practical form of any new invention. Now the inventor ia satisfied with the simplified co-oporatlun of the various departments, and a little later this plant will be enlarged to 500 tons capacity and converted into a custom mill. This represents an outlay of possibly $200,000. It will treat only the Knight ores. The great low-grade deposits of Iron Blossom, Dragon, Beck Tunnel will maintain it at capacity for fifteen to twenty years to come. These alone should furnish handsome profits of at least $2 per ton." (Eureka Reporter, September 11, 1914)
December 26, 1914
From the Salt Lake Herald, December 26, 1914
One of the largest machinery orders that has been placed in many months has been given the Traylor Engineering & Manufacturing company of Allentown, Pa., by the Knight-Christensen Metallurgical company which is constructing the mill at Silver City, says the Eureka Reporter. The order is to be filled at once and the machinery sent to Utah. With the new equipment the company will have a 100-ton mill and all the machinery will be permanent.
The present plant is to be completely overhauled and all the temporary machinery will be removed. One of the main “pieces of machinery will be a new roaster. The present roaster which was made in Utah, it is declared, was not made true enough to work properly. For that reason another roaster is being made. The other equipment will be new rolls for the fine grinding, screens, leaching tanks and a process of electric precipitation.
It is declared that the Christensen process has passed through the experiment stages and that the newly equipped plant will be able to handle the ore. After more than a year of experimenting with the process and testing-out various kinds of machinery it is now declared that it has reached a commercial basis.
It is expected that the machinery will be in and the plant started to grinding on ore during the early part of next year.
April 3, 1915
The Knight-Christensen mill at Silver City was destroyed by fire, for a loss of $50,000. (Eureka Reporter, April 9, 1915, "Saturday evening of last week")
On April 6, 1915, before certain mechanical difficulties could be overcome, the plant was destroyed by fire. Reconstruction began on the site of the abandoned Tintic smelter in July, 1915, by the Tintic Milling Co., newly organized by a consolidation of the Knight-Christensen Metallurgical Co. and the Mines Operating Co., which had operated successfully for two years at Park City, using the Holt-Dern process of roasting. The new mill was at first equipped with three Holt-Dern roasters and one Christensen roaster. The latter was discarded and eight more Holt-Dern roasters were added in 1916, when operations on a commercial scale began. (Geology And Ore Deposits Of The Tintic Mining District, Utah, USGS Professional Paper 107, 1919, page 117)
Mines Operating Company
(The following is based on numerous newspapers reports throughout the period, including an article in the July 30, 1914 issue of the Salt Lake Mining Review.)
The Mines Operating company had been operating in Park City since 1913, when the company leased the old workings in the Ontario mine, and leased and commenced rebuilding the Ontario mill which had been idle for a number of years. Although the company had been in operation since at least October 1911, it was formally incorporated as a Wyoming corporation on April 4, 1912. George Dern was general manager, and concidered to be an expert in the cyanidation process based on his experience as the current general manager of the Consolidated Mercur Gold Mines company.
The old equipment inside the Ontario mill was removed and new equipment purchased and installed. The rebuilt mill went into operation during the last week of September 1912, processing low-grade gold ore that had been used as fill in the stopes in the old workings of the Ontario mine that had been left behind. The mill operated only on occasional basis while the process to recover value from the low-grade ore was modified during numerous shut-downs.
By March 1913, the process had been perfected and the mill was producing its design capacity of 150 tons of gold concentrate per day. In April 1913, the mill shipped 86 tons of concentrate, employing 40 men in the mine, and 40 men in the mill. There were complaints from the community cooncerning the sulphur fumes coming from the mill as a result of its milling process. By March 1914, the process at Park City was being compared to the Christensen process in use at te Knight mill in Silver City, but with changes made in the process by George Dern. The new process was labeled as the Holt-Dern process, named for George Dern, general manager, and Theodore P. Holt, general superintendent. The mill was closed in November 1914 for a complete remodeling.
June 13, 1915
In the last weekly report of Parks City that included the Mines Operating company, the company was shown as shipping 201 tons of concentrate. (Salt Lake Herald, June 13, 1915)
June 26, 1915
"The Park City Mines Operating company has no longer any interests in this city. This week all the machinery installed by the company in the Ontario mill was taken out and is being shipped to Silver City, Tintic district to be used In the Knight-Dern mill being erected at that place. It is too bad that more favorable contracts could not have been made with the Ontario people by the Mines Operating company for the process was a proved success." (Park Record, June 26, 1915)
July 11, 1915
"Hauling of machinery from the Mines Operating company property at Park City has been commenced and soon all that can be utilized to advantage will be on the site chosen at Tintic for the erection of the 300-ton plant of the Tintic Milling company. The contract has been let for all the excavation for the new mill, and the intention of General Manager George H. Dern is to hurry the construction work so as to have the new mill operating if possible by January 1." (Salt Lake Herald, July 11, 1915)
December 18, 1915
"On account of the Mines Operating company being unable to continue work at the Ontario mine under the lease agreeement and the low price of silver, it was decided to abandone the work and the plant was moved to Tintic to be used in the construction of a mill for the Tintic Milling company. The plant was successful but the grade of ore was lower than expected and the price of metal made the profits too small for successful operation." (Deseret News, December 18, 1915)
Tintic Milling Company
(1915-1923)
Reconstruction of the Knight mill was to commence immediately, but instead a proposition was offered to the Knight concern by the Mines Operating Company of Park City, a George Dern venture. The Knight and Dern interests united in the construction of a mill on the site of the old Tintic Smelter that used the Holt-Dern process of roasting which had operated successfully for two years at Park City. V. C. Heikes described the process as follows:
"Briefly the process consists in roasting a mixture of ores, salt, and powdered coal, condensing the acid roaster gases in salt solution, leaching the roasted ore with this solution, and precipitating the metals on scrap iron." (Heikes, History of Mining, page 117)
The following description of the process comes from the Salt Lake Haerld, November 14, 1915.
The Tintic mining district produced, up to the end of the year 1914, ore valued at over $154,000,000. In mining it the various companies encountered ore that would not pay to ship to the smelters. Tremendous tonnages of that ore have been left in the various properties awaiting the advent of some process that would treat it at a profit to the companies.
The facts that the Tintic ores are of a highly silicious nature causes the smelter charges to be higher than the ores of a better fluxing nature. Only the higher grade ores can be mined and shipped direct to the smelters. There are several millions of tons of low-grade ore, that is, ore that cannot be shipped at a profit, standing in the following mines: Bullion Beck, Black Jack, Beck Tunnel, Carisa, Centennial Eureka, Eureka Hill, Iron Blossom, Chief Consolidated, Colorado, Dragon, Eagle & Blue Bell, Gold Chain, Grand Central, Mammoth and the Victoria.
When these facts were brought to the attention of N. C. Christensen, Jr., and Theodore P. Holt, metallurgists who had been working on a process for the treatment of low-grade silicious ores, a series of elaborate tests were made on the Tintic ores. The tests proved satisfactory from practically every point of view, and as a result the Tintic Milling Company was formed. The process had been discovered in 1911 and had been worked out on a small scale by the Mines Operating Company in the Park City, Utah, district.
It was perfected and standardized by March, 1914, and the plant at that time was treating 150 tons per day and getting an extraction of about 75 per cent of the values. This was being done with a crude hand-operated furnace.
The present mill that is being constructed at Silver City in the Tintic district will have a daily capacity of 300 tons. By adding additional roasting facilities and leaching vats the capacity can be readily brought up to 500 tons per day. It is steel-concrete mill and modern in every detail.
June 25, 1915
The following comes from the Eureka Reporter, June 25, 1915.
Will Start Work On Tintic's Mill. -- Knight and Dern interests have worked out all details pertaining to big mill which is to be built at Silver City. -- Excavating for the new mill of Tintic Milling Co. will no doubt be started by the first of July, or just as soon as the equipment of the old Tintic Smelting Co can be removed from the ground upon which the new concentrating plant is to be erected. This new corporation - the Tintic Milling Co. - takes over the assets of the Knight-Christensen Metallurgical Co. and the Mines Operating Co. and the articles of incorporation, which have just been filed, place the capitalization at $30,000, divided into 1,000,000 shares of the par value of 3 cents. The Knight interests will have control of company, owning 51 per cent of the stock, but George Dern will be the general manager of the company.
The officers are as follows: Jesse Knight, president; George Dern, vice president and general manager; W. Lester Mangum, secretary and treasurer and Theodore P. Holt, general superintendent.
In taking over what is left of the Knight-Christensen plant, destroyed by fire some months ago, the new company will also take over the contracts that the company has for the treatment of ore from all of the Knight mines, including the Iron Blossom, Dragon, Beck Tunnel, Colorado and Black Jack. Stockholders of the Mines Operating Co., of Park City, will have a chance to get into the new milling company on the same basis as Mr. Dern, provided they make application before the first of July. The report of the Mines Operating Co. shows that owing to the low price of silver and the poor grade of ore secured from the Park City mine, where the mill is located, there was a loss during the latter part of last year. The company's indebtedness will be wiped out by the disposal of some property to the new Tintic Milling Co.
The machinery from the Park City plant and the mill at Silver City, together with the $30,000 that has been subscribed for the new stock, should go a long way toward the construction of the new mill which will start off with a capacity of 300 tons. It will no doubt be but a very short time until the mill is enlarged to 1000 tons.
June 30, 1915
"The Tintic Milling Company, of Provo, Utah, has been incorporated with a capitalization of $30,000 divided into 3-cent shares. The officers and directors are: Jesse Knight, president; Geo. H. Dern, vice-president and general manager; W. Lester Mangum, secretary and treasurer; J. William Knight and James C. Dick. The company will build a milling plant in Tintic district, Utah, utilizing the Knight-Dern process of ore reduction." (Salt Lake Mining Review, June 30, 1915)
Work began in July 1915, with Alexander McDonald of Eureka contracted to do excavation and concrete work. By March 1916, break-in work was being done; and in April the mill had proven a success. Initially equipped with three Holt-Dern roasters and one Christensen roaster, in 1916, when commercial operations commenced, eight more Holt-Dern roasters were added in place of the Christensen mechanism. By January 1918, the mill was shipping two bullion cars per month. (Eureka Reporter, December 4, 1914; May 14, 1915; May 21, 1915; July 16, 1915; August 20, 1915; March 17, 1916; April 7, 1916; January 25, 1918; February 22, 1918; March 1, 1918)
November 30, 1915
The following comes from the November 30, 1915 issue of the Salt Lake Mining Review.
Low Grade Ores Of Tintic. - Fred C. Dern of Salt Lake has the following to say regarding the low-grade ores of the Tintic, Utah, district, and of the history of the new mill now being constructed to treat those ores: The Tintic mining district produced, up to the end of the year 1914, ore valued at over $154,000,000. In mining it the various companies encountered ore that would not pay to ship to the smelters. Tremendous tonnages of that ore have been left in the various properties awaiting the advent of some process that would treat it at a profit to the companies.
The facts that the Tintic ores are of a highly siliceous nature causes the smelter charges to be higher than the ores of a better fluxing nature. Only the higher grade ores can be mined and shipped direct to the smelters. There are several millions of tons of low-grade ore, that is, ore that cannot be shipped at a profit, standing in the following mines: Bullion Beck, Black Jack, Beck Tunnel, Carisa, Centennial Eureka, Eureka Hill, Iron Blossom, Chief Consolidated, Colorado, Dragon, Eagle & Blue Bell, Gold Chain, Grand Central, Mammoth and the Victoria.
When these facts were brought to the attention of N. C. Christensen, Jr., and Theodore P. Holt, metallurgists who had been working on a process for the treatment of low-grade siliceous ores, a series of elaborate tests were made on the Tintic ores. The tests proved satisfactory from practically every point of view, and as a result the Tintic Milling Company was formed. The process had been discovered in 1911 and had been worked out on a small a scale by the Mines Operating Company in a the Park City, Utah, district.
It was perfected and standardized by March, 1914, and the plant at that time was treating 150 tons per day and getting an extraction of about 75 per cent of the values. This was being done with a crude hand operated furnace.
The present mill, that is being constructed at Silver City in the Tintic district will have a daily capacity of 300 tons. By adding additional roasting facilities and leaching vats the capacity can be readily brought up to 500 tons per day. It is steel-concrete mill and modern in every detail.
January 15, 1916
"The Mines Operation Company, formerly of Park City, Utah, and the Knight-Christensen Metallurgical Company, whose mill at Silver City burned down, have joined interests under the name of the Tintic Milling Company and are now erecting a 300-ton plant at Silver City. Jesse Knight is president of the new concern, and George H. Dern is general manager. The plant is to treat the lowgrade ores of the district by the roasting and chloridizing process, and is expected to be in operation some time in February." (Salt Lake Mining Review, January 15, 1916)
February 15, 1916
"The new plant of the Tintic Milling Company at Silver City, Utah, is now completed and will soon be handling ore. It has a capacity of 300 tons a day." (Salt Lake Mining Review, February 15, 1916)
September 15, 1916
"General Manager George H. Dern, of the Tintic Milling Company, states that the plant of the company at Silver City, Utah, will be brought up to full capacity of 300 tons a day within sixty days. Six of the new Holt-Dern roasters have been delivered at the property, and the other two should be there by the middle of the month. Metallurgists who have visited the plant say that the problem of treating the low grade siliceous silver-copper ores of the district has been solved by the process in. use. The plant is at present handling eighty-five tons a day, coming principally from the Iron Blossom and Dragon Consolidated properties." (Salt Lake Mining Review, September 15, 1916)
May 30, 1919
"It is reported that Geo. H. Dern of Salt Lake has sold his interest in the Tintic Milling Company, operating at Silver City, Utah, to the Jesse Knight interests." (Salt Lake Mining Review, May 30, 1919)
September 15, 1923
"The plant of the Tintic Milling Company, located at Silver City, is to suspend operations. Lyman Baker, the superintendent, says that the mill has ceased receiving and crushing ore but that the greater part of the month will doubtless elapse before a cleanup in all departments of the mill can be brought about." (Salt Lake Mining View, September 15, 1923)
(The reason given was that, because the major amount of ore received and processed was silver ore, and the mines were not producing due to the slump in silver prices, resulting in the mill was not receiving adequate amounts of ore to make a reasonable profit.)
December 15, 1924
Tailings of the Tintic Milling Company were being loaded into rail cars and shipped to the Asarco smelter in Salt Lake Valley. On the first day of operation of a steam shovel, 500 tons was loaded into 10 rail cars. (Salt Lake Mining Review, December 15, 1924)
1926
The Tintic Milling company had ceased operating in about 1926, "about eight years ago" from 1934. The structures were slowly being dismantled by thieves, so the structures at the mill site were dismantled and the materials moved to the site of the North Lily mine, which was also owned by the same parent company. (Eureka Reporter, March 12, 1954, "Tewnty Years Ago")
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