Alaska Freegold Blue Ribbon Mine, Alaska
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This page will provide information about the Blue Ribbon Mine. A little history, a little production, and little geology. (Note: This page written by Dennis R. Garrett, who bears sole responsibility for the accuracy of the statements herein. This page is for information only.)
Preface: I first came to what would become The Blue Ribbon Mine in 1985. The first reported mining in what was to become The Blue Ribbon Mine took place in 1906. Except for some stretches when no mining took place, some gold has probably been recovered every year since. The total amount recovered is unknown, but at least 20,000 ounces have been reported recovered, mostly by small-scale hand or mechanized methods. At least that much, and probably more, remain. The Blue Ribbon Mine is located on a road that takes off at the end of the Petersville Road, T28N-T29N, and R8W-R9W, Seward Meridian, Alaska. See U.S.G.S. Talkeetna C-2 quadrangle map for details. Today, over one hundred years since the first gold rush in south-central Alaska, a renewed interest is taking place in the Yentna mining district. This report will focus on one mine, abandoned when the owners were murdered in 1939, and reopened in 1992.The mine is located on Gopher Gulch, a tributary of Willow Creek and Ramsdyke Creek; We also have claims or interests on Poorman Creek; Cottonwood Creek; Peters Creek, and some on no creeks above these; and on tributaries of Cache Creek to the south. In 1990 I began an earnest search for the possible lode sources of the placer gold found in the streams draining the eastern flanks of the northern Dutch Hills. One source, the major one in fact, turned out to be the abandoned mine known as 'The Potato Patch'. This report will describe that deposit, and include information released as as recently as 2 months ago. That information will include results of an airborne geophysical survey and related ground-truth follow up studies, and occurences discovered by this author and not previously described in the available literature. I will be regularly adding to and updating this page. Most recent update: 11 June 1999 (minor edits 11 Jan 2008). Note: This will be a stripped-down version of the Mineral Property Evaluation Report compiled on the subject property. That report is available from the author. * Blue Ribbon Mine as used in this report includes those claims on Gopher Mountain, located in sections 24 and 25, T29N R9W of the Seward Meridian, Alaska. This report is not to be construed as a solicitation for the sale of securities. Such solicitation may only be done through a prospectus. This report is for information on the companys business, projects, and properties. INTRODUCTION. The recent release of an Airborne Geophysical Survey and follow up ground-truthing surveys, coincident with the discovery of additional veins and mineralized outcrops in and around the Blue Ribbon Mine, has spurred a renewal of exploration of the mineral potential of the area. This report will focus on the known mineralization, history, and past production, and finally how this new information fits into the model. The southern part of the Chulitna-Yentna mineral belt, reported on by Clark and Hawley in USGS Professional Paper 758-A, lies within the Yentna Mining District. The known portion "..extends from a few miles south of Collinsville to the Tokositna River;" on the north. Geography and Environment: Located in the transition zone between Maritime and Continental climatic zones. The topography is dominated by the high, spectacularly glaciated Alaska Range, which forms a northeast-trending arc of mountains in this part of Alaska. North Americas' tallest mountain lies approx. 30 miles to the northwest. South-central Alaska Range foothills, of low vertical relief (1800' - 4000' above sea level), is the primary topography within the property, which is located on the eastern flank of the Dutch Hills. Precipitation is relatively high, (average annual rainfall is 30" and average mean annual snowfall is about 130") owing to the barrier created by the Alaska Range. Temperature ranges from +70o F in the summer to -20oF in winter. The region is protected from the harsh continental extremes of the Interior by the Alaska Range. Vegetation is primarily sub-alpine brush or mosses, and a few stunted trees are widely scattered about. Existing environmental baseline data are incomplete at this time. History and Past Production : Gold was first reported in the area in 1898, and claim staking and production had begun on this property by 1906. Three operations were being conducted on Willow Creek and two of its' headwater tributaries, Gopher and Ruby Gulch, by 1917. It is known that at least 1500 ounces of gold was produced from an area smaller than 320 by 660 feet. About 2000 ounces were reported produced from Little Willow Creek, which drains the Potato patch area in the mid-30's. Hydrauliking and hand-mining operations continued yearly under then-owners Frank and Helena Jenkins, until 1939, when they and 2 other persons were murdered on these claims. Since1992, pilot-plant and bulk testing of the area known as the "Potato Patch" has been conducted. Click HERE for a picture of some of the gold. The area was actively prospected and mined before WWII. Essentially no new exploration work was done from the early '50s' until 1972, (except for Clark and Hawley, USGS 1968) when the price of gold started to move up. A number of reports, both Government and private, have been generated since then, and new data are being generated from recent surveys conducted by the Alaska Division of Geological and Geophysical Surveys and this author. The following excerpt is from a report written in 1973:
Except for the "very small amount of actual decomposed material handled", the tailings left are primarily larger rocks piled up after being thrown from the sluice or pit. The other claims that make up this property, on the west and north sides of Gopher Mountain, were mined at some time by persons unknown. They are included in this report whenever it is referring to the Blue Ribbon Mine, unless otherwise noted. The geology and other features are the same. Numerous lode claims were staked at various times in the past, and some work was done, but all evidence in the field has long since been lost, as is the case with most, if not all, of the written documentation. Current Development : Pilot-plant testing of the "Potato Patch", including test pits, equipment, settling ponds, and other infrastructure is in place, with camp facilities. All permits, licenses, etc. are current for 1999. Refer to narrative below for details and mining method. NOTE: Details of this report pertaining to reserves, assays, ore grades, and other proprietary information have been deleted. Geologic nature of the exploration target : Lode deposits, primarily auriferous quartz veins in slate and argillite, shear zones, and other mineralized areas have assayed from a few ppm { Parts per million. 1 ppm = 1 gram/metric tonne } to XX.5 oz/ton. This is no doubt an anomalous high reading. An unusual number of samples have assayed at ~0.3 oz/ton, after visible gold was removed. See Table of Results for details. An unknown amount of lode gold was produced from the property. Estimated >1.5 million tons in shear zones, veins, and mineralized areas. Unknown volume of auriferous alluvial and bench gravels, grading at 0.0xx ounces of gold per yard. Closer examination of this deposit is indicated. Quantity and quality of information : The author endeavored to obtain all information available, from any source, and this was accomplished before verification began. A review of published material relating to the property was accomplished as part of the initial study and reconnaissance program, and the information thus obtained was a great time saver, as some details of regional and local geology has been worked out previously by qualified observers. Please refer to References and Acknowledgements. Except for x0,000 cubic yards of economic grade gold bearing gravels, which is limited to those areas on both sides of Gopher Gulch, the remainder of the deposit must be classified as "uninvestigated" or "underinvestigated", at least as far as required for the classification of reserves. Detailed exploration, in an increasing level of collection and analysis, is indicated. Regional Geology : Most of this information taken from or based on U.S. Geological Survey Map I-1174, Geologic Map of the Talkeetna Quadrangle, Alaska, by Bruce Reed and Steven Nelson, and from U.S. Geological Survey Open-File report #68-1, Clark and Hawley, unless otherwise noted. SURFICIAL DEPOSITS
SEDIMENTARY and VOLCANIC ROCKS
One of these zones has been traced over eight miles, trending approx. N42oE, the same as the main fault zones in this area, and is known to be a significant source of placer gold. More about this is presented in the section on resources.
This author has discovered a number of previously undescribed igneous occurences and altered zones. A brief description of them follows:
TOP REFERENCES As most of the references are listed in the reports noted below, the reader is advised to review the references listed in these reports. U.S. Geological Survey, Circular 775; Bull. 520, p. 174-200; Bull. 534 p. 75; Bull 773-A, p. A63-A69. Open-File Report # 68-35. Geologic Map of the Talkeenta Quadrangle, I-1174. Professional Paper 758-A; U.S. Bureau of Mines Open-File Report # 24-78. NEAR SURFACE PLACER DEPOSIT MODEL and Proposed Low-Sulfide Gold Quartz Vein Model The near surface placer deposit model evaluated herein is based on current geologic knowledge of the Blue Ribbon Mine Project placer and lode deposit and nearby placer and lode deposits in the Dutch Hills, Alaska. For details see the part of the Mineral Property Evaluation Report describing these deposits. The geometry of the deposit is horizontally oriented and generally tabular in shape. The ore body is buried by a maximum of 4' of overburden, which consists of unfrozen glacial till, glacially derived fluvial sediments, and soil with vegetative matter. The ore body is composed of fluvially deposited, well-to poorly sorted gravel, and the gold is disseminated throughout the ore body, with some concentration on the bedrock, and the gold may extend 2' into the bedrock. The bedrock is a weathered, gray or green-gray pebbly conglomerate of Tertiary age (unit Tps) which is itself gold-bearing, or where this conglomerate has been removed by erosion, the bedrock is a slate or graywacke of late Jurassic or early Cretaceous age (unit Kjs). Swell factor of the gravel is estimated to be 20%. Ore body dimensions are from 4' to 15' thick, up to 300' wide, and of variable length. Stripping factor averages .27:1. The mining and reclamation plan is based on open-pit, mechanical cut-and-fill techniques. Pit walls are designed for a maximum 45 degree slope. Mining occurs up to 140 days per year at a maximum of 16 hours per day, @ 60LCY (loose cubic yards) per hour. Any overburden is stripped by bulldozers and stockpiled for future reclamation. Process water is 100% recycle, and makeup process water (to compensate for evaporation and other losses) is obtained from seepage infiltration into the pit and runoff from rain. Ore is excavated by bulldozers or hydraulic excavators, transported by bulldozers or front end loaders, and fed to the plant by hydraulic excavator or front end loader. Average one-way haul distances are less than 100'. The initial processing plant will consist of a feed hopper, shaking screen or trommel, sluices, and a waste conveyor. Concentrates recovered from the sluices are further processed on-site by jigs and/or shaking tables, and further processed by the best available technology to produce several grades of concentrate and enhance co-product recovery. Sluice and/or jig tailings are caught in a series of ponds, dewatered, and stockpiled for future reclamation, and the water is reused for processing. Excess surface and groundwater is diverted around the operation. Reclamation is conducted as much as possible concurrent to the mining operation. Pits, settling ponds, and other mine infrastructure are stabilized prior to the end-of-season closure. See attached diagram. Exploration to support the mining operation will continue ahead of the operation in the direction of mining to define the limits of the pay zone as well as to determine the parameters of the processing operations, which will be modified as needed to achieve maximum recovery. Final closure of the mine site will occur when the ore is exhausted, and will consist of final grading of the tailings and spreading of the organic overburden, reseeding the site, and removal of the mine equipment and surface structures. Proposed Low-Sulfide Gold Quartz Vein Model (Go To Part 2-In Progress 10 June 1999)
Back to Top The current status of the mine and associated reserves are as follows: Equipment on-site consists of a Drott 35D excavator, trommel washplant, a 30 LCY/hr testplant, a 25 LCY/hr testplant, (either may be used as a small production plant), a 70 yd/hr trommel plant, a D-6 and a D-7 "Cat" dozer(s), (1) each 4" and 6" pumps, and misc. support equipment and camp facilities too extensive to list. The equipment on-site is generally in good to very good condition, and the additional equipment needed to scale up to full production is available and ready to mobilize to the site. Other equipment, needing repairs, is available. The mine infrastructure consists of several small pits, from which gold and other metals have been produced, settling ponds, tailing piles, ditches, test pits, some stripped ground, access roads, an access road from the Petersville Road, a good landing strip, and a number of cabins, trailer campers, and other buildings. Permits have been applied for and received for test or pilot plant operations for the years 1988-99, and should present no problem in the future. Adjusted value-A sample value that has been increased or decreased by an amount deemed necessary to offset known variables or other factors that may cause discrepancies in the initially collected value. See indicated value. Alluvial-1. Deposited by a stream or river. 2. Relating to deposits made by flowing water. Assay-To determine the amount of metal contained in an ore. Au Chemical symbol for gold Auriferous-Containing gold. Batholith-A large plutonic intrusive body at least partially igneous, the bottom of which is not clearly marked, and with margins that are often gradational and that widen with depth. BCY -Bank Cubic Yard, the measurement of gravels in place. See also LCY and Swell Factor. One cubic yard is 27 cubic feet. Bedrock-The solid rock underlying auriferous deposits. The term bedrock may be applied to any consolidated formation underlying the gold-bearing gravel. See also false bedrock. Bench Deposit-Gravel deposits in ancient stream channels which are above the present streams. Black Sand-Heavy grains of various minerals which have a dark color, and are usually found with gold in placer deposits. Blue Gravel-Some of the deeper, water-saturated gravels have a distinctive bluish-gray color. At one time they were believed to represent a separate gravel flow, distinct from the overlying red gravels. Actually, these blue gravels represent unoxidized portions of the gravel channels, whereas the red gravels represent the oxidized portions of the same material. Eluvial Deposit or Eluvium-Loose material resulting from the decomposition of rock. Eluvial material may have slumped or washed downhill for a short distance, but it has not been transported by a stream. Eocene-An epoch of the Tertiary period between the Paleocene and Oligocene. False Bedrock-A hard or relatively tight formation within a placer deposit, at some distance above the true bedrock, upon which gold concentrations are found. Clay, volcanic ash, or tight gravel formations can serve as false bedrock. A deposit may have gold concentrations on one or more false bedrocks, with or without a concentration on true bedrock. Fineness-The proportion of pure gold expressed in parts per thousand. For example, a piece of natural gold containing 150 parts of silver and 50 parts of copper per thousand, and the remainder pure gold, would be 800 fine. Float-Piece of ore or rock which have fallen from veins or strata, or have been separated from the parent vein or strata by weathering agencies. Fluvial-Of or pertaining to streams or rivers. Gangue-The noneconomic mineral components of a mineral deposit. Glacial-Pertaining to, characteristic of, produced or deposited by, or derived from a glacier. Gm-Gram Greisen-Igneous rock that has been altered by the action of fluids rich in volatile elements. Hydrothermal Vein-A vein formed by the crystallization of minerals from predominantly hot water solutions of igneous origin. Indicated Value-The value of a placer sample before making adjustments for shaft factors, boulder factors, or other empirical corrections. Lacustrine-Deposits Deposits formed in the bottom of a lake. Overburden-Worthless or subeconomic surface material covering an ore deposit. Oz-Ounce, Troy More to Come! Back to the top of the page.
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