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Occurrence Details

Occurrence Number
115I 169
Occurrence Name
Occurrence Type

General Information

Primary Commodities: gold, silver
Aliases: Guder, Freegold
Deposit Type(s): Skarn Au
Location(s): 62.290490 N, -137.1355 W
NTS Mapsheet(s): 115I06
Location Comments: Coordinates provided by Triumph Gold in 2020.
Hand Samples Available at YGS: No


Work History

The original discovery in the Mt. Freegold area was made by P.F. Guder in 1930 on the Augusta cl (15494), followed by discoveries on the adjoining Peerless, Gold Star and Margarete claims. Guder explored by hand pits and shallow shafts until 1959. Guder's claims (Gold Star group) were optioned in 1969 to Yukon Revenue Mines Ltd and in 1973 to Prism Resources Ltd., which did a magnetometer survey and staked an additional 100 claims - PFG, AG, etc (Y75468) in June-September.

Prism transferred the option early in 1974 to Dynasty Exploration Ltd., which explored by grid soil sampling, a ground magnetic geophysical survey and trenching later in the year. Guder's claims were optioned by Arctic Red Resources Corporation from 1980 to 1982, then transferred to Guder Mining Exploration Ltd. The Guder and Harris claims were optioned in 1986 by Chevron Minerals Ltd., which conducted a grid geochemical and EM survey, and in 1987 by Big Creek Joint Venture (Big Creek Resources Ltd and Rexford Minerals Ltd), which explored with extensive bulldozer and excavator trenching, a VLF-EM and magnetometer survey and geochemistry in 1987 and minor trenching in 1988. The claims were transferred back to Harris in September 1989.

Gagan Gold Corporation optioned the property and explored with trenching and two rotary holes (122 m) in 1991. Redell Mining Corporation optioned the Goldstar property from Harris and Associates in August 1994. In September 1995, Pauline cl (YB37987) and Goldstar cl 1-3 (YB37988) were transferred to B. Harris.

Northern Freegold Resources consolidated the claims in 2006 as part of their Golden Revenue property and performed a property wide VTEM and magnetic airborne survey, including the Augusta occurrence.

Triumph Gold acquired Northern Freegold Resources in 2015 and the property that includes the Augusta occurrence is now termed the Freegold Mountain Project.

Regional & Property Geology

The occurrence is partly underlain by Yukon-Tanana Terrane (YTT). The rocks of the YTT in this region consist of Early Mississippian metamorphic rocks separated into meta-sedimentary and meta-igneous suites. The meta-sedimentary suite consists of micaceous quartz-feldspar gneiss, schist and quartzite. The meta-igneous package is comprised of biotite-hornblende feldspar gneiss and coarse-grained granodiorite orthogneiss with lesser amphibolite.

The YTT basement rocks are cut by numerous plutonic and volcanic events from the Mesozoic (Murray & Friend, 2018), including:
1. Early Jurassic Long Lake monzonite to syenite plutonic suites;
2. Mid-Cretaceous Mount Nansen Suite andesite to diorite;
3. Mid-Cretaceous Whitehorse granodiorite, quartz monzonite and granite;
4. Late Cretaceous Casino quartz monzonite;
5. Late Cretaceous Prospector Mountain syenite; and,
6. Quartz feldspar and feldspar hornblende porphyry dykes and plugs.

The major structural feature in the area is the Big Creek Fault with steeply-dipping, northwest-trending dextral faults parallel to the more regional Tintina and Denali faults (AR 097175).

Gold bearing veins at Augusta occur in a roof pendant of Paleozoic metasedimentary rocks enclosed in Mesozoic syenite and granodiorite and intruded by Cretaceous porphyry dykes. The metamorphic rocks consist of quartz-feldspar-mica-chlorite gneiss and schist, and minor marble, amphibolite and quartzite (AR 093019).

Mineralization & Results

At the Augusta showing, pods of magnetite skarn 1 to 5 m wide are concordant with the foliation and are traceable for about 100 m to the northwest. The primary skarn assemblage consists of magnetite, epidote, diopside, red and brown garnet and calcite and carries trace gold (0.03 g/t) and minor silver (0.2 g/t). Locally superimposed on the primary skarn is a retrograde assemblage of quartz, hematite, actinolite and chlorite which returns erratic high gold and silver values. The original Augusta mineralization consisted of free gold found within surface samples of highly oxidized, vuggy and limonitic coated magnetite. Massive fresh magnetite usually carries low gold values (AR 092127).

A 5 m chip sample from a 1987 trench assayed 366 g/t Au and 106 g/t Ag over 5 m. Shallow drilling failed to confirm such high grades, although hole 87-15 assayed 4.5 g/t Au and 46.3 g/t Ag over 6 m (AR 091896).

Drill holes 91-5 and 91-6 in 1991 tested for a northwest extension of the Augusta zone, with negative results (AR 093019).

Location Map

Last Updated: Dec 23, 2020

Work History

Year Work Type Comment
2006 Airborne Geophysics: Magnetic Property wide survey.
2006 Airborne Geophysics: VTEM Property wide survey.
1991 Drilling: Rotary Two holes totaling 122 m.
1991 Geochemistry: Rock
1991 Trenching: Mechanical
1988 Geochemistry: Rock
1988 Trenching: Mechanical
1987 Geochemistry: Rock
1987 Ground Geophysics: Magnetics And VLF-EM.
1987 Trenching: Mechanical
1986 Geochemistry: Soil
1986 Ground Geophysics: EM
1974 Geochemistry: Soil
1974 Ground Geophysics: Magnetics
1974 Trenching: Mechanical
1973 Ground Geophysics: Magnetics

Regional Geology - Terrane


Regional Geology - Bedrock

Period Max:
Age Max: MA
Period Min:
Age Min: MA
Rock Major:
Rock Minor:
Geological Unit (1M):
Geological Unit (250K):

Related References

Number Title Page(s) Document Type
093019 Rotary Percussion Drilling and Trenching Assessment Report on the Goldstar Property Assessment Report
YEG2017_4 New contributions to the bedrock geology of the Mount Freegold district, Dawson Range, Yukon (NTS 115I/2, 6 and 7) Annual Report Paper
092699 Trenching Program on the Goldstar Property Assessment Report
091896 Report on Geological Mapping and Geochemical and Geophysical Surveys Done on the Goldstar Property Assessment Report
2018-2 Bedrock geological map of the Mount Freegold district, Dawson Range Open File (Geological - Bedrock)
092127 Trenching, Geophysical and Diamond Drilling Program on the Goldstar Property Assessment Report
097175 Drilling and Geochemical Report on the Freegold Mountain Project Assessment Report
Last Updated: Dec 23, 2020


Year Zone Type Commodity Grade Tonnage Amount Reported Amount 43-101 Compliant Cut-off
1986 Augusta (Open Pit) Historical Estimate gold 4.11 g/t 70,760 No No Unknown
1986 Augusta (Open Pit) Historical Estimate silver 103.88 g/t 70,760 No No Unknown

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