During the summer of 1862 the Oro Fino Vein on top of War Eagle Mountain was discovered. During 1863 a number of lode claims were located and mining in earnest began. The strike of the Oro Fino Vein System, covers approximately 10,000 feet in length, and 2,000 feet in depth. Approximately 85 % of the "known" and "mapped" vein has not yet been mined. By the end of year 1875 a total of ten shafts had been sunk on the vein ranging in depth from 300 feet to 1250 feet. The Oro Fino Shaft at the North is 300 feet deep and the Mahogany Shaft at the South is 1100 feet deep. The Golden Chariot and Ida Elmore shafts are 1250 feet and 1000 feet respectively. By the end of 1875, 415,000 ounces of gold equivalent had been extracted from these shafts.
Why did mining suddenly cease on War Eagle Mountain ?
During the fall and winter of 1874 the owners of the Golden Chariot mine completely refurbished the shaft and mill equipment, effectively "betting the ranch" on the secure knowledge that the Oro Fino Vein continued uninterrupted for a considerable distance. Production in the mine started again in early spring of 1875.
In August 1875, the Financial Panic that had started in New York in 1873, culminated with the San Francisco Bank crash, and then the San Francisco Stock Exchange closure. A nationwide depression was in full swing. At the height of the mining boom on the Oro Fino Vein, the source of working capital for the mines dried up. The miners continued to work through October 1875, but because they had not been paid, they left the mountain for employment elsewhere. During the winter of 1875-1876 the shafts filled with water to a point that the Golden Chariot Shaft contained 1100 feet of standing water. The water level in all the shafts on the Oro Fino Vein stands at approximately the 7,300 feet elevation. This condition has existed for the past 131 years, which has resulted in the preservation of this historical vein system without it being disturbed by intruders or miners.
The mine, the ore veins, and the shafts are "as-they- were" in the fall of 1875...at the height of the mining boom....untouched, for more than a century...a "Rip-Van-Winkle" situation.
During the productive life of the Oro Fino Vein System from 1863 through 1875 the crude mining and milling methods, utilizing pan and plate amalgamation and chlorination, resulted in poor recoveries. They recovered less than 75 Percent of the gold and silver. At this recovery level the cut-off rate for lifting ore to the surface for milling had to be at least 2 ounces per ton. Today we can make a profit at .375 ounces per ton. All the veins showing less than 2 ounces per ton were abandoned or bypassed.
The Oro Fino Veins are compressed between very stable granite rock formations, which means the shafts, drifts, and stopes left by the old time miners are free standing and still in mining-ready condition. The principal Oro Fino Vein can be described by thinking of War Eagle Mountain as a loaf of bread that has been tilted sidewise 8 degrees. Now consider that one slice of bread
represents the Oro Fino Vein which is 2000 feet deep and up to 10,000 feet long.
Of the three peaks that form a contiguous fault trend, and whose mines all show the same veins, i.e., Delamar Mountain, Florida Mountain, and War Eagle Mountain ; Delamar and Florida were purchased by Kinross Gold Corporation ( KGC ) , which operated a profitable open-pit mining operation on Delamar Mountain until the late 1990s.
From 1875 through 1899 mining men who had managed and worked in the underground mines and milling operations tried to promote a project that would allow them to recover the remaining submerged gold and silver reserves they new existed within the water filled workings. Finally, in November 1899, American Smelting and Refining Company (ASARCO) funded the SinkerTunnel Project. The project objective was to drive a 10x 10 tunnel from Sinker Creek on the North-East side of War Eagle Mountain, at an elevation of 5200 feet, approximately 2000 feet below the bottom of the Golden Chariot Shaft. This tunnel was named THE SINKER TUNNEL. It's intended use was to drain water out of War Eagle Mountain and to haul ore mined from the veins to the surface for milling. The cost of the project was a staggering $ 250,000; in today's terms, this equals approximately $ 25,000,000.
It was anticipated that the tunnel would intersect the Oro Fino Vein at about 7000 feet from the tunnel portal. The vein was actually intersected at 6890 feet during May 1902.The tunnel was extended north about 80 feet. At this point a raise was started upwards toward the bottom of the Golden Chariot Shaft. When this raise reached 620 feet in height it was only 150 feet below the bottom of the Golden Chariot Shaft, which contains 1100 feet of water at about 600 psi. At this point the amount of water permeating down into the raise was increasing every day. The miners became anxious about their safety, and concerns arose as to just "how" ASARCO planned to punch the final hole into the bottom of the Golden Chariot shaft. They sent a representative to Boise to inform the Idaho Inspector of Mines about the working conditions. He inspected the mine raise and stopped any further work in that area until safety measures were in place.
At that time, early (1905), ASARCO was a very large mining company with prospects and projects all over the world. Management elected to close the project down, put it on the shelf and return later if conditions changed. ASARCO never returned. During 1932 and 1933 some additional exploration tunnels were driven to the north and to the south from the raise. In 1941, salvagers opened the Sinker Tunnel and removed all the steel rail and pipe scrap for the war effort. Shortly thereafter, a landslide buried the tunnel under more than 50 feet of rock, and the complex was forgotten.
In 1994, the current owners rediscovered the location of the tunnel, and over a period of several years, excavated the entrance, and refurbished the complex, with the exception of the upper four levels of the raise, nearest to the bottom of the Golden Chariot shaft. The entrance was strengthened, and a permanent structure was built to protect the site. In addition, the entire length of the tunnel was restored, complete with efficient ventilation and made accessible by small vehicles to the very end. The roads to the Complex were upgraded to allow 25-ton trucks access to the site, and an area 300x400 feet was prepared to act as a staging area at the 7350 foot level.
These mines produced fabulous wealth in the first few years because the surface deposits were of extraordinary richness. As the mines got deeper the veins had a smaller yet more consistent amount of ore in relation to the amount of rock that needed to be removed to expose it. Generally, the value of ore per ton of rock removed remained consistent from a depth of 150 feet to as deep as any of the mines were worked, or over 1,200 feet. This would indicate that the extensions of the veins into the deeper levels, not yet reached by the mine shafts, should contain the same percentage of metal ore.
The mines became more expensive to develop and operate as they got deeper. This was not due to the value of ore per ton, but more significantly, it was a result of the increased cost of lifting the ores and water from greater depth to the surface for processing and disposal. The removal of ground water in mines is a persistent expense that must be addressed on a daily basis. When a mine doesn't have a lower working level tunnel - i.e., the Sinker Tunnel Complex - that intersects a vertical shaft, the water must be brought to the surface and disposed of no matter what the expense or technical inconvenience if the mine is to continue operating. This increased cost of mining at depth was one of the most significant problems for the mines on War Eagle Mountain. Modern pumping techniques, or the Company's access to the Sinker Tunnel Complex, solve this problem.
The final event that was responsible for the closing of the rich mines on War Eagle Mountain was a major economic depression that began in New York in 1873 with the failure of the Jay Cooke and Company Bank. This serious depression spread westward across the United States causing major business failures and finally reached the West Coast in late 1875. The failure of the Bank of California and the San Francisco Stock Exchange Board was simply more than the mines could endure. Many of the early mines cut back operations or shut down within a matter of months, never to seriously operate again.