California Mining Journal (PH 16-11)(July 1937) (30 pages)

California Mining Journal, July, 1937 THREE What Happens to the Gold By V. L. ZACHERT METALLURGICAL ENGINEER 78 Wcodland Ave., San Francisco ROM the beginning of time, gold was recovered in its native state from placers. Placer mining is the simplest and most attractive means of acquiring the treasure which nature holds in store for those inclined to be industrious and thrifty. However, simple as placer mining appears, its present methcd of recovering gold is very wasteful and far from efficient. Gold, as found in placers, exists in various physical conditions, such as nuggets, gold in coarse grains and also in minute divided particles commonly termed fine gold. In the process of washing gold-bearing gravel, nuggets are the easiest to recover due to their extreme heaviness. The coarse grains and fine gold, however, require the use of quicksilver to aid their separation and collection from the gravel. The amount of gold in gravel that it pays to mine is extremely minute. A gold content of ten cents per cubic yard of gravel yields a handsome profit by the dredging system of mining when handling ten thousand cubic yards of gravel per day. This means that 30,000,000 pounds of gravel must be worked each day to obtain about 20 ounces of gold—a ratio of 15,000,000 to 1 of gold. Quicksilver Not a Catch-All Many who are engaged in dredging or other form of placer mining are under the impression that the main object required in order to obtain a satisfactory recovery of gold, is to get the quicksilver in the riffles to unite with the gold where it will remain in the form of amalgam, and that it is then as safe as in a vault with no further thought of same until clean-up time. But on careful consideration it becomes apparent that the long interval to the clean-up time is quite detrimental to a good gold recovery, due to the fact, observed in many instances, that amalgam very often shows up in the last riffle of the tail sluice. Frequent Clean-ups Advised This latter action is explained by the theory that’ after a long period of run, the .riffles become overcharged with amalgam which eventually will work its way down the sluice and into the tailings. Permitting the accumulation of any _ considerable amount of amalgam on the dredger is accompanied with serious economic disadvantages and possible heavy loss due to theft. For these several reasons the old established practice in dredging to clean up at short intervals of about every ten days is still carried on. Much to Learn Abcut Recovery While working out a gold recovery problem for a dredging concern in California that had serious gold losses in their dredging operations the writer had an opportunity of discovering many unrecorded mysteries affecting gold recoveries that transpired from the time that the dredger bucket dumps its load of gold-bearing gravel on the dredger to the point where the material runs out on the waste dump. One of the most conspicuous and serious observations noted was that considerable amalgam made its appearance on the last riffle of the tail sluice after a run of only two days following a clean-up. This led to further investigation, the result of which demonstrated that under certain conditions MARGINAL MINES AND WAGES In announcing the closing of the Original Amador Mines, at Amador City, where 100 men lost their jobs, S. E. Woodworth, one of the operators, stated: “Just as the mine operated at a loss several years ago with $20.67 gold and a $3.50 wage, so it will now with $35 gold and a $5.00 wage.” LOS ANGELES NOTES R. H. Toll, mining engineer, with headquarters in Los Angeles, has been on a combined business and pleasure trip, extending from Siskiyou County, Calif., to Chicago, Ill. On June 5 he was on the way to southwestern Colorado for a month or two. His address will be Hesperus, Colo. F. E. Calkins, economic geologist, has been visiting in Los Angeles and has returned to Wallace, Idaho. John Herman, Los.Angeles chemist, has been recently engaged on plant ash research. He found almost uniform small definite amounts of silver in potato ashes, and thinks that minute amounts of metal may be a necessity just as copper is in the human body, the metals presumably acting as catalysts. STATE COMPENSATION FUND HAS ASSETS OF OVER 14 MILLIONS Industrial accident commissioner Frank C, MacDonald advises that the state compensation insurance fund, which is conducted under supervision of the industrial accident ccmmission, now has assets totaling $14,336,811.29. This surpasses any previous record of the fund. The premiums written during the first quarter of 1937 amounted to $2,539,813.10, which was a gain of $662,000 over the premiums for the first quarter of 1936, and is an increase of 35 per cent. In addition to having $12,147,295 invested in gilt edge state and federal bonds for the state fund, has $1,498,000 in cash and shortterm U. S. treasury notes. Starting with a fund of $100,000 loaned to the Fund by the State, this enormous sum in surplus and reserve, plus the rebates to the insured, averaging 27 pct. of their premium, demonstrates that rates are entirely too high for an institution founded to give employers insurance at cost. Everett D. Gorman, who mined at Michigan Bluff, Placer Co., for 40 years, passed away at Auburn, June 12: age, 78. SIERRA COUNTY The Oriental mine, Alleghany, is building a modern clubhouse for its employees, Don Steger of Nevada City having the contract. At the Plumbago mine south of Alleghany, a sinking program is in progress, Plans call for installation of larger hoists and heavier machinery. Ten stamps of the twenty-stamp improper understanding of the properties of quicksilver and its relation to gold amalgamation may be detrimental to high recovery of gold. This phenomenon will be gone into more fully in a subsequent article. mill are working three shifts, and the company will install flotation later on. Men are employed cutting timber from the burned over area between the Plumbago and Irelan mines which fire destroyed about two years ago. F. W. Siddall, manager of the Shamrock Gold Mining Co., with property adjoining the Ruby mine in Sierra County, has resumed operations on what was formerly the Lost Mexican claims. Resumption will be on a modest but steady basis. The mine is owned by two groups of investors, one in San Francisco and the other in Tacoma. EE REDMAN SCIENTIFIC CO. Distributors of Laboratory Supplies Reagent Chemicals Baker & Adamson Chemicals Central Scientific Co. Specialties 585—587 HOWARD ST. SAN FRANCISCO Garfield 1408 UROOUOUEQOQEOETOTUQUQUONEQOOUOOOOUGOOOENOOECEONTLL AlRandWATER PIPE * FOR EFFECTIVE VENTILATING: SIZES: 3 to 14-inch Galvanized Lockseam, made up or K. D. 10-ft. Lengths, By-Passes, Fittings. Fight Silicosis Costs by Blowing Clean Air to Your Men Also LOCK SEAM Surface Pipe and Permanent Pipe for Low Pressure WATER LINES * W.R. AMES CO. 150 Hocper St., San Francisco Tell Your Machinery or Hardware Dealer You Must Have .. AMES QUALITY CUOTTUUUUQQOQNGOOOOTOOULUYOQQQUOQOQGUEETTOUOUAUAAANAN JOY & COMPANY Distributors INDUSTRIAL OILS and GREASES + + + QUENCHING OILS—SOLUBLE OILS Cutting and Grinding Compounds HYDRAULIC COMPOUNDS Sulphurized Lard Base Thread Cutting Oils Cable Grease—Extreme Pressure Oils + + + MAIN 10150 1616 20th Street, Sacramento, Calif.

California Mining Journal, July, 1937 THREE What Happens to the Gold By V. L. ZACHERT METALLURGICAL ENGINEER 78 Wcodland Ave., San Francisco ROM the beginning of time, gold was recovered in its native state from placers. Placer mining is the simplest and most attractive means of acquiring the treasure which nature holds in store for those inclined to be industrious and thrifty. However, simple as placer mining appears, its present methcd of recovering gold is very wasteful and far from efficient. Gold, as found in placers, exists in various physical conditions, such as nuggets, gold in coarse grains and also in minute divided particles commonly termed fine gold. In the process of washing gold-bearing gravel, nuggets are the easiest to recover due to their extreme heaviness. The coarse grains and fine gold, however, require the use of quicksilver to aid their separation and collection from the gravel. The amount of gold in gravel that it pays to mine is extremely minute. A gold content of ten cents per cubic yard of gravel yields a handsome profit by the dredging system of mining when handling ten thousand cubic yards of gravel per day. This means that 30,000,000 pounds of gravel must be worked each day to obtain about 20 ounces of gold—a ratio of 15,000,000 to 1 of gold. Quicksilver Not a Catch-All Many who are engaged in dredging or other form of placer mining are under the impression that the main object required in order to obtain a satisfactory recovery of gold, is to get the quicksilver in the riffles to unite with the gold where it will remain in the form of amalgam, and that it is then as safe as in a vault with no further thought of same until clean-up time. But on careful consideration it becomes apparent that the long interval to the clean-up time is quite detrimental to a good gold recovery, due to the fact, observed in many instances, that amalgam very often shows up in the last riffle of the tail sluice. Frequent Clean-ups Advised This latter action is explained by the theory that’ after a long period of run, the .riffles become overcharged with amalgam which eventually will work its way down the sluice and into the tailings. Permitting the accumulation of any _ considerable amount of amalgam on the dredger is accompanied with serious economic disadvantages and possible heavy loss due to theft. For these several reasons the old established practice in dredging to clean up at short intervals of about every ten days is still carried on. Much to Learn Abcut Recovery While working out a gold recovery problem for a dredging concern in California that had serious gold losses in their dredging operations the writer had an opportunity of discovering many unrecorded mysteries affecting gold recoveries that transpired from the time that the dredger bucket dumps its load of gold-bearing gravel on the dredger to the point where the material runs out on the waste dump. One of the most conspicuous and serious observations noted was that considerable amalgam made its appearance on the last riffle of the tail sluice after a run of only two days following a clean-up. This led to further investigation, the result of which demonstrated that under certain conditions MARGINAL MINES AND WAGES In announcing the closing of the Original Amador Mines, at Amador City, where 100 men lost their jobs, S. E. Woodworth, one of the operators, stated: “Just as the mine operated at a loss several years ago with $20.67 gold and a $3.50 wage, so it will now with $35 gold and a $5.00 wage.” LOS ANGELES NOTES R. H. Toll, mining engineer, with headquarters in Los Angeles, has been on a combined business and pleasure trip, extending from Siskiyou County, Calif., to Chicago, Ill. On June 5 he was on the way to southwestern Colorado for a month or two. His address will be Hesperus, Colo. F. E. Calkins, economic geologist, has been visiting in Los Angeles and has returned to Wallace, Idaho. John Herman, Los.Angeles chemist, has been recently engaged on plant ash research. He found almost uniform small definite amounts of silver in potato ashes, and thinks that minute amounts of metal may be a necessity just as copper is in the human body, the metals presumably acting as

catalysts. STATE COMPENSATION FUND HAS ASSETS OF OVER 14 MILLIONS Industrial accident commissioner Frank C, MacDonald advises that the state compensation insurance fund, which is conducted under supervision of the industrial accident ccmmission, now has assets totaling $14,336,811.29. This surpasses any previous record of the fund. The premiums written during the first quarter of 1937 amounted to $2,539,813.10, which was a gain of $662,000 over the premiums for the first quarter of 1936, and is an increase of 35 per cent. In addition to having $12,147,295 invested in gilt edge state and federal bonds for the state fund, has $1,498,000 in cash and shortterm U. S. treasury notes. Starting with a fund of $100,000 loaned to the Fund by the State, this enormous sum in surplus and reserve, plus the rebates to the insured, averaging 27 pct. of their premium, demonstrates that rates are entirely too high for an institution founded to give employers insurance at cost. Everett D. Gorman, who mined at Michigan Bluff, Placer Co., for 40 years, passed away at Auburn, June 12: age, 78. SIERRA COUNTY The Oriental mine, Alleghany, is building a modern clubhouse for its employees, Don Steger of Nevada City having the contract. At the Plumbago mine south of Alleghany, a sinking program is in progress, Plans call for installation of larger hoists and heavier machinery. Ten stamps of the twenty-stamp improper understanding of the properties of quicksilver and its relation to gold amalgamation may be detrimental to high recovery of gold. This phenomenon will be gone into more fully in a subsequent article. mill are working three shifts, and the company will install flotation later on. Men are employed cutting timber from the burned over area between the Plumbago and Irelan mines which fire destroyed about two years ago. F. W. Siddall, manager of the Shamrock Gold Mining Co., with property adjoining the Ruby mine in Sierra County, has resumed operations on what was formerly the Lost Mexican claims. Resumption will be on a modest but steady basis. The mine is owned by two groups of investors, one in San Francisco and the other in Tacoma. EE REDMAN SCIENTIFIC CO. Distributors of Laboratory Supplies Reagent Chemicals Baker & Adamson Chemicals Central Scientific Co. Specialties 585—587 HOWARD ST. SAN FRANCISCO Garfield 1408 UROOUOUEQOQEOETOTUQUQUONEQOOUOOOOUGOOOENOOECEONTLL AlRandWATER PIPE * FOR EFFECTIVE VENTILATING: SIZES: 3 to 14-inch Galvanized Lockseam, made up or K. D. 10-ft. Lengths, By-Passes, Fittings. Fight Silicosis Costs by Blowing Clean Air to Your Men Also LOCK SEAM Surface Pipe and Permanent Pipe for Low Pressure WATER LINES * W.R. AMES CO. 150 Hocper St., San Francisco Tell Your Machinery or Hardware Dealer You Must Have .... AMES QUALITY CUOTTUUUUQQOQNGOOOOTOOULUYOQQQUOQOQGUEETTOUOUAUAAANAN JOY & COMPANY Distributors INDUSTRIAL OILS and GREASES + + + QUENCHING OILS—SOLUBLE OILS Cutting and Grinding Compounds HYDRAULIC COMPOUNDS Sulphurized Lard Base Thread Cutting Oils Cable Grease—Extreme Pressure Oils + + + MAIN 10150 1616 20th Street, Sacramento, Calif.