NEVADA DAILY TRANSCRIPT
PUBLISHED DAILY (MONDAYS EXCEPTED
[Masthead information not transcribed]
NEVADA COUNTY OFFICIAL PRESS
WEDNESDAY OCTOBER 17, 1883.
Personal Reminiscences—Character of the Ores—Processes Applied to Reduce Them—“Gold is Where You Find It.”
EDITOR TRANSCRIPT; The discovery of ore in Meadow Lake District was the result of an excavation for the purpose of constructing a dam for the water storage of one of the large hydraulic companies on the San Juan ridge. The ores were peculiar. Nothing resembling them had come under the observations of the prospector. The fissures were well defined on the surface, but the experience of the Excelsior and other companies proved that they were not permanent in depth.
The country rock of the district is granite. The ores are generally black in color, due to the presence of iron. Near the surface at the California group of mines was a spongy looking rock resembling scoria. In this, small flakes of gold were visible, but they were not thicker than gold leaf. There also occur red large masses of white iron pyrites, known to the Cornish miner as “Mundie.” This substance was supposed to be rebellious or refractory ore, containing fabulous proportions of gold. Pack trains of twenty or more mules were laden with this stuff, which was delivered at Virginia City or Grass Valley for treatment, but no results were returned, a fire assays failed to prove the presence of any precious metal. Local metallurgists met with no better success. They were in such haste to erect works that they did not waste time in making assays, but on the completion of their works they learned a practical lesson in metallurgy—that they couldn’t get gold where it did not exist. G. F. Deetkin, well known in Nevada county as an experienced metallurgist, was one of the victims of the illusion.
Then came the era of “processes.” We heard of many processes, notably the [illegible], which was discovered by a lady. The chemical principle of this process was the use of a solution of chloride of sodium in a novel manner. The “Hagen process was purely a mechanical invention—a stirring apparatus in a reverbatory furnace. In 1874 there came to California a young mechanical engineer, Robert M. Fryer. He had been engaged in erecting machinery in the Southern States, and had his attention directed to the sulphuret ores of North Carolina and Georgia, upon which he had made some experiments by roasting in bulk—that is, without crushing. This, however, was not his incentive in coming to California. He had been informed that our mountain streams contained vast deposits of sulphuretted tailings, very rich in gold, and only awaiting some method of concentration to give up the absorbed treasure. On his arrival in San Francisco he commenced experimenting upon tailings without success—or at least without discovering any practical method of handling the substance economically. His attention being drawn to the so-called refractory ores of Meadow Lake he reverted to his experiments in the Southern States, and from them evolved the “Fryer Process.”
Residents of Grass Valley and Nevada City in 1875, will remember the structure erected near the Halfway House, devoted to a mysterious process for the treatment of gold and silver bearing ores. The process at that time consisted of about 24 feet of miner’s sheet iron pipe, 12 inches diameter, suspended upright, and a miner’s pan on a block of wood as a moveable bottom. This was the roasting apparatus. Supplementary to the “roaster” was a crushing apparatus of simple and novel device. It was a section of cast iron pipe column, such as is used in the Cornish system of pumping water from mines. It was about 10 feet long and 10 inches in diameter. This cylinder was closed at both ends by an iron cap. The roasted ore and a cylindrical piece of iron was placed in this section of pump column, and the pipe was revolved the long way, the iron weight acting as a crusher and grinder.
Such was the mechanism. The process was as simple as the machinery. Kindling wood and shavings were thrown in the upright pipe; on top of this pile of fuel the 25 pounds of ore to be worked was thrown in, after being “spalled” to walnut size. The fuel was ignited from the bottom of the pipe, which constituted the furnace. When the fuel burnt out the roasted ore dropped into the miner’s pan. It was not in a state for trituration by the revolving cylinder, aided by the sliding weight. When the roasted ore had been reduced to a fine state (usually in two hours) the quicksilver and a few gallons of warm water was added for purposes of amalgamation. In two hours more the charge was drawn and the amalgam washed out and retorted. The tendency of the quicksilver to “sicken” or flour was corrected by the addition of some simple chemicals not necessary to mention here. By this simple process, which is now patented, rebellious ores were worked on a small scale to an average of from 80 to 90 per cent. of their assay value. It was in fact an approximate assay on a large scale. The percentage “won” was determined by a fire assay of the tailings.
The results of these experiments induced Mr. Fryer to acquire for his company so-called mines of rebellious or refractory ore, and his attention was drawn to Meadow Lake District. His agent, Jas. Wallace, acquired by relocation most of the abandoned mines. Nearly all of the wood-piles in the country were bought for fuel and a large water jacket furnace was built at the works, supposed to have a capacity of 16 tons per 24 hours. Dr. Henry DeGroot, an able mining writer, produced a pamphlet entitles “Meadow Lake—The City of a Day,” and Fryer stock jumped from $10 to $40 per share in less than thirty days. In July, 1876, Fryer bought the canvass covering which extended over the principal block in Grass Valley to shield the orators and spectators from the midsummer sun of the 100th anniversary of our Independence. The canvas was to be used for tents to shelter the numerous engineers and employees who were to dig out the rich ores of Meadow Lake. Wagon loads of ore were brought from the mines and treated in the big furnace. The result was “microscopic.” If anything was proven it was that under proper conditions the Meadow Lake ores would make excellent fuel, for one charge which was to have been finished in ix hours burned for six days, during which time the explosion of gasses in the furnace reminded the amazed employees of the eruption of a volcano.
The average value of Meadow Lake ores, as demonstrated by hundreds of fire assays, regardless of process treatment, was from $5 to $7 per ton. There are now hundreds of sacked samples of these ores on the Fryer grounds. Let those who are in doubt investigate for themselves. W. A. S.
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