The Sunshine Mine is located between the towns of Kellogg and Wallace in northern Idaho. It has become one of the largest and most profitable silver mines in the world, having generated more than 360 million ounces of silver since 2001.
Canadian Report 2007 by Behre Dolbear & amp; The company estimates measured and indicated resources of 31.51 million ounces of silver in 1.43 million tonnes at 21.8 ounces of silver per ton and an implied resource of 231.5 million ounces of silver at 2.28 million tonnes at 101.6 ounces silver per ton. The Behre Dolbear report is considered historic in nature and illustrates the resource potential of the Sunshine Mine.
From a historical record beginning in 1904, the Sunshine Mine produced 364,893,421 ounces of silver from 12,953,045 tonnes ore until 2001 when the mine closed. From 1 January 1998 to 1 January 2004, the average mine carrying amount was 1.38 million tons containing 32.20 million ounces of silver at 23.3 oz Ag/tonne.
Video Sunshine Mine
Histori Edit
Sejarah awal Edit
The Sunshine Mine property had its beginnings in 1884. In September of that year two brothers with the names of True and Dennis Blake filed claims for a series of ore deposits in Big Creek mining district in Shoshone County, Idaho. The Blake Brothers, as they are often called collectively, are a native of Maine. In the autumn of 1876, for reasons not mentioned in extant sources, the Blake Brothers began migrating west. They lived and worked in Chicago for some time before proceeding west and settling in the Washington Territory. According to court records, Blake Brothers lived in Snohomish County, Washington Region in October 1878. However, Blakes was not long in the Washington Territory. Sometime after November 1879, the brothers moved to the eastern part of the region, settling in the small town of Spokane Falls. In early 1880, Blakes moved back to Coeur d'Alene Valley in Idaho where they lived at the mouth of a river called Big Creek; located in the middle between the cities of Kellogg and Wallace now. Here Blakes farmed for several years, until, in September 1884, they happened to find the ore deposits at Big Creek Canyon from their homestead.
It was this deposit, the Lode Yankee mining claim, that Blake's brothers lurked at the end of September 1884. The brothers mined their claims over the next two decades until poor health persuaded them to release control of the property for other purposes. After True Blake's death in 1910, widow True Hattie Blake and her brother Dennis Blake chose to lease the mining property. The property was leased to several people at a time or sometime in September 1912. The property underwent a series of acquisitions in subsequent years, leased and managed at various times by people such as Sidney Shonts and then Dan Price.
Price, President of Big Creek Leasing Company, extended a large sum of money trying to reach ore reserves at a lower rate than previous Blake Brothers jobs. Prove unsuccessful in this endeavor. The price attracted a Spokane businessman by the name of Eugene Tousley. Tousley, in turn, is interested in Yakima businessman, a businessman and a Washington mining entrepreneur named John Sawbridge. It is unclear exactly when Sawbridge was involved in the company, but he probably held a stake in the company when the Sunshine Mining Company was officially formed in 1918. At present the company's headquarters are in Spokane, Washington. The company's original officers were Eugene C. Tousley, E. Ely, and V.S. Ricaby. Tousley is a broker in the mining industry, working in Spokane. During this time, W.F. Newton is the manager of the company
Around 1921, a group of businessmen and entrepreneurs from Yakima, Washington purchased a controlling stake in the Sunshine Mining Company. John Sawbridge becomes and/or remains the President of the Company. The Yakima businessman who joins the current Board is Albert E. "A.E." Larson (entrepreneur and successful entrepreneur), Alexander Miller (civilian and business leader) and Nathan P. "N.P." Hull (leading Yakima initiator and businessman). Hull remained on the Board until his death in July 1929. Three years after his death, in 1932, the son of Hull Carroll M. Hull was appointed to the Council. Carroll Hull remained at the Sunshine Council until February 1965.
After Sawbridge's death in 1931, Larson became President and served the company in that capacity until his own death in 1934. At that time Robert M. Hardy (the original Yakima and President of the National Bank of Yakima) became President. He would remain president until his resignation in 1956, when his son succeeded him as President of the Company
In 1921, a 25 ton plant per day was built. The factory was then expanded little by little and eventually reached a daily capacity of 500 tons. As soon as the concentrator is assigned, the Sunshine tunnel is driven off the surface in an exploratory effort that finds high quality ores that have historically been identified as "Chinatown"
In 1935, the concentrator at the mine was upgraded with a new ball mill milling unit and flotation cell that increased the capacity up to 1,000 tonnes per day while achieving a 98% recovery. The sinking of the vertical Jewell shaft of four new compartments began, reaching 2300 levels in 1936.
In 1943, a crew drifted east at 2700 level after the Silver Syndicate fault found the famous Chester vein.
It was mainly the exploits of the Sunlight vein followed by the Chester vein that determines the current configuration of the underground workings. With the invention of Chester vein at 2700 level and the ore body distance of the Jewell axle about 4,000 feet east-southeast, other internal shafts (No 4, No 5 and No 10 shafts, more precisely defined as winzes) are sunk or raised to more efficiently serve operations. The other main internal axis is the No. axle. 12, Western Syndicate copper vein and vein service at the west end of the mine.
In 1957, under the Presidency of Robert M. Hardy Jr., Sunshine Mining Company drilled the Medina No. oil well. 1, located just north of Ocean City on the Washington State coast. This is a joint venture with J.W. Tanner who is a businessman from Olympia, Washington with a special interest in the oil industry. Sunshine Mining Company bought Tanner's interest in the company in 1958. Sunshine's Medina No. 1 will also produce 12,500 barrels of oil and remain the only oil producer in Washington state. In 1961 the well was closed and production ceased.
In 1960, a sand filling operation was introduced underground in the Sunshine Mine. Factory tailings are grouped so that crude materials, approximately 45% of the total factory feed, are used to replenish reinforcement.
Fire History and Next Edit
On the morning of May 2, 1972, a fire broke out in the Sunshine Mine. According to the US Mining Rescue Association, 91 workers died from smoke inhalation or carbon monoxide poisoning; 83 men rescued, 81 on May 2 and 2 on May 9th. The mine was closed for seven months after the fire, which is one of the worst mining disasters in American history and is the worst disaster in Idaho history. Today, the monument to the missing miners stands beside Interstate 90 near the mine.
After the disaster of May 1972, the mine closed for several months. However, when the mine reopens, production is full again and Sunshine regains its position as the number one silver producer on the Nation. In 1979 alone Sunshine Mine produced 18% of the silver ore of the Nation. By the end of 1988, the mine was in full operation. Ore production comes primarily from the mining of Chester's vein system serviced by No. axle. 10 and the remnants of Sunlight and Rambo are referred to as the Footwall area at levels 3700 and 3400. The copper vein 4000 and 4200 levels are being developed from the No. axle. 12.
In 1989, the mine produced 4.8 million ounces of silver. Production of high quality copper vein began to affect the silver production volume. During 1990, the mine produced 5.4 million ounces of silver, the largest since 1971. Currently, high-grade copper fiber stops at 4200 levels to become a major producer, while production from 10 shaft shafts decreases.
In 1991 the price of silver fell to $ 3.90 per ounce and the operation was losing money. The mining plan is put together to reduce losses substantially while waiting for the price to improve. It was referred to as a "small-mine plan" and was implemented in June 1991. The underground operation post was centered by closing remote, more expensive production and development outposts, and restricting operations to midday shifts only. Mining operations are consolidated in the copper vein area and the most productive title in the "Footwall Area". Mine below level 5000 is saved and left to be filled with water. Production is cut in half, while the labor force is reduced by 65%.
The West Chance vector was discovered in 1992. By the end of 1996 it was clear that ore bodies had enough size and value to support the return of mines to full production. The reserves are then developed with loopholes and lateral development methods using LHD (Load-Haul-Dump) equipment. The work area outside the Western Opportunity is closed and rescued regularly and all resources are directed towards the Western Opportunity. In July 1997, mineworks below the 4000 level were rescued from all equipment and materials that could be used and allowed to begin filling with water. In 1995, Sunshine acquired a neighboring Consolidated Silver (ConSil) property consisting of surface facilities and underground work of the Silver Summit Mine. This mine has served as the second access of the Sunshine Mine over the years. ConSil's underground mine works are mainly accessed by adit to an internal 5600-foot shaft. The opening of this adite surface is located about two miles east of the Jewell shaft.
Closure Edit
The mine halted production in the first quarter of 2001 due to several factors. These include low silver prices and lack of regular and consistent exploration and development because previous management shifted cash flow from the mine to corporate costs, debt and other projects.
At closing, the mine reserves are 1.13 million tonnes containing 26.75 million ounces of silver at 23.6 ounces of Ag/ton. Upon closure of the mine, these 'Historic' or 'Legacy reserves' are reclassified to 'mineralized materialization' as required by the US Securities and Exchange Commission regulations. These "Legacy Resources" are now classified as Mineral Resources under the CIM Definition Standards.
On November 2, 2009, Alberta Star Development Corp. announced that it has signed a binding term sheet with the Sterling Mining Company to acquire Sterling controlling holdings and assets and provide to finance Sterling's ongoing operations. The Alberta Star then halted their search for the mine in the face of competing interests.
On April 22, 2010, the Sterling Mining Company announced that Court documents would be submitted soon to approve a successful $ 24.0 million bid for the assets and shares of the Sterling Mining Company, the historic Sunshine Mine operator. Successful bidders - at a cash price of $ 24.0 million - are Silver Opportunity Partners LLC (SOP). SOP is a private company owned by Thomas Kaplan. He is based in New York as part of the Electrum Group of Companies, an international investor in a precious metal mine.
On February 14, 2012, the mine was evacuated after a sensor in the ventilation shaft detected an increase in carbon monoxide levels in it. Twelve people were underground at the time, at night. All of them are workers for underground mining service contractors called The Redpath Group, with headquarters in North Bay, Ontario, Canada. The mine was evacuated and sealed. All intake of oxygen into the mine must be closed, and nitrogen is injected to reduce oxygen levels and extinguish the fire. On June 12, 2012, working under the guidance of the federal Mine Safety and Health Administration (MSHA), the seal was broken on the shaft and the crew reached a level of 3,100 feet of mine where the fire began to fire. A gas reading of 3,100 levels indicates no carbon monoxide and proper oxygen levels, indicating that the fire is out.
Maps Sunshine Mine
Geology Edit
The district is guided by the rocks of the Super Pre-Cambrian Belt group, divided into Prichard groups, the Ravalli group, the Central Carbonate group, and the Missoula group. The Ravalli group contains the Revette and St. Regis which is the preferred parent rock for silver mineralization in the district. The ore deposit is localized in St. The 600-square-foot Regis and the upper part of the Revette's 3,000-foot base formation. The contact between the formation is unclear and locally selected as the bottom of the most distinct purple interval in St. Regis. Rock types include argillite, siltite, quiteite sericite, and vitreous quartzite.
Infrastructure Edit
The Sunshine Mine Infrastructure is ancient and will require repair and renovation. Water supply and electricity are sufficient for short-term future use. Access property is with a 2-mile paved parallel county road that cuts Interstate 90 US. Communications, including telephone installed and operated.
Mineralization Edit
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