Quadrangle map, 1:250,000-scale | LG |
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Quadrangle map, 1:63,360-scale | A-2 |
Latitude | 65.0459 |
Longitude | -147.562 |
Nearby scientific data | Find additional scientific data near this location |
Location and accuracy | The True North Mine is about 2 miles northwest of Pedro Dome. The coordinates are near the center of several open pits which are spread over an area about 2 kilometers in diameter. The mine is near the center of section 33, T. 3 N., R. 1 E of the Fairbanks Meridian. The old Hindenburg/Markovich Mine (LG054) became part of the True North Mine. |
Geologic descriptionThe True North gold mine is a structurally controlled, disseminated gold deposit on the northwest flank of Pedro Dome (Masterman, 1998). Gold was recognized on the property as early as 1913, but early production was limited to stibnite ore from the Hindenburg/Markovich Mine (ARDF site LG054), which became part of the True North Mine.
The mineralization at True North consists of thin quartz-carbonate veins, often with stibnite, in a heterogeneous, high-grade metamorphic package of calcareous eclogite, carbonaceous schist and quartzite (Swainbank and others, 1998). Gold occurs in a northeast-trending zone, 2,500 feet wide and 5.000 feet long, west of the northeast-trending Eldorado Fault. Gold-bearing ore bodies are typically 20 to 60 feet thick in gently dipping shear zones and along faulted lithologic contacts (Masterman, 1998). Alteration is characterized by quartz, manganese-oxides, ankerite, mariposite, sericite, and carbon. The gold grade averages 0.05 to 0.10 ounce of gold per ton (Masterman, 1998). The mineralization is probably 90 Ma, the same age of many deposits in the vicinity.
Exploration activities at the True North from 1991 to 1997 consisted of 9,832 top-of-bedrock soil samples, 15,621 feet of trenching, 40,133 feet of core drilling, and 153,914 feet of reverse-circulation drilling (Masterman, 1998). Soils were auger sampled in 1998 (Szumigala and Swainbank, 1999, p. 10).
In 1999, Kinross Gold Corporation acquired the True North property (Quandt and others, 2008). By 2008, the prospect consisted of a large block of State of Alaska claims that Kinross Gold Corporation had leased from several private individuals. Open-pit mining began at True North in April, 2001, and the mine eventually consisted of several large open pits spread over an area about 2 kilometers in diameter; the ore was trucked to the Fort Knox mill (FB115). In 2004, mining was suspended. From 2001 to 2004, the True North Mine had shipped 11,026,722 tons of ore to the mill. By 2009, permits had been submitted to close the mine, all the mine buildings had been removed, and revegetation of the mine workings had begun. Quandt and others (2008) estimated that the True North deposit had an indicated resource of 3.464 million tons with a grade of 1.49 grams of gold per tonne. This estimate was done to modern industry standards. These figures were published after the mine had ceased production and was in the process of being closed. | |
Geologic map unit | (-147.564446216362, 65.0454736074351) |
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Mineral deposit model | Disseminated carbonate-replacement gold mineralization associated with intrusion- and schist-hosted crushed veins and low-angle shears. |
Age of mineralization | About 90 Ma based on analogy with similar gold deposits nearby. |
Alteration of deposit | Alteration is characterized by quartz, manganese-oxides, ankerite, mariposite, sericite, and carbon. |
Workings or exploration |
The following history of exploration is based on an abstract presented by Steve Masterman, Newmont Exploration Limited, at the 1998 Alaska Miners Association Meeting. In 1990, Dick Swainbank brought the property to the attention of AMAX Gold, Inc. (AGI). AGI acquired the claims and conducted soil sampling, trenching, and 6,332 feet of reverse-circulation (RC) drilling. In 1994, after drilling 14 more RC holes under an exploration agreement, LaTeko acquired the property from AGI. During the summer of 1994, LaTeko expanded the soil grid, excavated additional trenches, drilled 52,000 feet of RC and 2,040 feet of HQ core. In 1995, Newmont Exploration Ltd. began exploration on the property,after entering into a joint venture with LaTeko. Exploration activities on the True North property from 1991 to 1997 consisted of 9,832 top-of-bedrock soil samples, 15,621 feet of trenching, 40,133 feet of core drilling, and 153,914 feet of RC drilling (Masterman, 1998). In 1998, most exploration work consisted of soil sampling by auger (Szumigala and Swainbank, 1999, p. 10).
In 1999, Kinross Gold Corporation acquired the True North property (Quandt and others, 2008). By 2008, it consisted of a large block of State of Alaska claims that Kinross Gold Corporation had leased from several private individuals. Mining began at True North in April, 2001 and the ore was trucked to the Fort Knox mill (FB115). Mining was suspended in 2004. In 2009, final reclamation at True North began (Szumigala and others, 2010). |
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Indication of production | None |
Reserve estimates | Quandt and others (2008) estimated that the True North deposit had an indicated resource of 3.464 million tons with a grade of 1.49 grams of gold per tonne. This estimate was done to modern industry standards. These figures were published after the mine had ceased production and was in the process of being closed. |
Production notes |
From 2001 to 2004, the last year of production, the True North Mine had shipped 11,026,772 tons of ore to the mill. In 2009, Fairbanks Gold Mining, Inc., the operator of True North Mine, made the decision to forego further mining and exploration at the site, and began final reclamation (Fairbanks Gold Mining, Inc, 2012, and Alaska Department of Natural Resources, 2014). |
Additional commentsIn 2009, Fairbanks Gold Mining, Inc., the operator of True North Mine, made the decision to forego further mining and exploration at the site, and began final reclamation. In 2010, 149 acres of the site were graded, growth media was placed on 52 acres, and 270 acres were scarified, seeded, and fertilized. By 2011, the major earthwork was completed leaving a small area of materials to be salvaged. As of summer 2014 the site was essentially fully revegetated and will be monitored for several more years to assure long-term stability (Fairbanks Gold Mining, Inc, 2012, and Alaska Department of Natural Resources, 2014). |
MRDS Number | 10307720 |
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ReferencesMasterman, S. S., 1998, The True North gold project, Fairbanks mining district, Alaska [abs.], in Extended abstracts of the 16th biennial conference on Alaskan mining: Alaska Miners Association Annual Meeting, March, 1998, Fairbanks, Alaska.
Quandt, David, Ekstrom, Chris, and Triebel, Klaus, 2008, Technical report for the Fort Knox Mine: Unpublished Technical Report, 79 p. (posted on www.sedar.com, March 31, 2008).
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Reporters | C.J. Freeman, J.R. Guidetti Schaefer (Avalon Development Corporation); D.J. Grybeck (Contractor, USGS); V.C. Zinno (Alaska Earth Sciences, Inc.) |
Last report date | 9/1/2014 |