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Occurrence Details

Occurrence Number
115I 184
Occurrence Name
Jilly Bob
Occurrence Type

General Information

Secondary Commodities: gold, silver
Aliases: Freegold
Deposit Type(s): Epithermal Au-Ag: Low Sulphidation
Location(s): 62.321150 N, -137.1739 W
NTS Mapsheet(s): 115I06
Location Comments: Coordinates provided by Triumph Gold in 2020.
Hand Samples Available at YGS: No


Work History

Staked as the Seymour cl 1-44 (YA60053) in May 1981 by Arctic Red Resources Ltd and in 1985 by Chevron Minerals Ltd who carried out geochemical sampling and bedrock mapping.

In 1987, Chevron optioned its claims to Big Creek Joint Venture (Big Creek Resources Ltd. and Rexford Minerals Ltd.). Big Creek Resources Ltd. purchased the claims in the spring of 1990. Rinsey Mines Ltd. optioned Big Creek's claims in February 1991.

ATAC Resources re-staked the area in 1999 and conducted soil and rock geochemistry, prospecting and ground magnetic geophysical survey near the Jilly Bob showing. ATAC carried out soil and rock geochemistry in 2002 and 2004, as well as hand and mechanical trenching in 2004.

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 Jilly Bob occurrence. In 2013, Northern Freegold Resources carried out soil, silt and rock geochemistry, as well as mechanical trenching.

Triumph Gold acquired Northern Freegold Resources in 2015 and the property that includes the Jilly Bob 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).

Mineralization & Results

The Jilly Bob showing was discovered in 2002 uphill from a gold soil anomaly. It consists of 070° striking, southeast dipping quartz veins hosted in silicified metasedimentary rocks and adjacent to quartz feldspar porphyry dykes. The quartz veins range from 0.1 m to 1.8 m wide and have been traced for 100 m along strike (Paulter, 2006; AR 094528).

Sampling in 2002 of drusy, pitted quartz float located along the road in the area returned 2 380 ppb Au, 2 374 ppm Ag, 7 610 ppm Pb, 2 900 ppm Bi and 490 ppm Sb. No outcrop exists in the area and only small fragments of highly decomposed wallrock float occur with the mineralized quartz (AR 091823).

Trenching and sampling in 2004 noted gold bearing quartz veins, as well as disseminated and fracture-fill mineralization (Paulter, 2006). Trenching results returned elevated gold and silver with TRS04-06: 3.25 g/t Au and 573 g/t Ag over 1.8m in TRS04-06; 0.228 g/t Au, and 142 g/t Ag over 0.7m in TRS04-07; 0.432 g/t Au and 9.83 g/t Ag over 7m, including 9.79 g/t Au and 106 g/t Ag over 0.1 m in TRS04-09 (AR 094528).

No significant results were noted in the 2013 trenching and sampling by Northern Freegold Resources.

Location Map

Last Updated: Jan 6, 2021

Work History

Year Work Type Comment
2013 Geochemistry: Rock Chip and grab samples.
2013 Geochemistry: Soil And silt geochemistry.
2013 Trenching: Mechanical
2006 Airborne Geophysics: Magnetic Property wide survey.
2006 Airborne Geophysics: VTEM Property wide survey.
2004 Geochemistry: Rock Grab and chip samples from trenches.
2004 Geochemistry: Soil
2004 Trenching: Hand
2004 Trenching: Mechanical Four trenches.
2002 Geochemistry: Rock Grab sampling.
2002 Geochemistry: Soil
1999 Geochemistry: Rock Prospecting grab samples.
1999 Geochemistry: Soil
1999 Ground Geophysics: Magnetics
1985 Geochemistry: Rock Prospecting grab samples.
1985 Geochemistry: Soil
1985 Geology: Bedrock Mapping

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
094040 Prospecting, Soil Geochemistry, and Magnetic Surveys on the Seymour Property Assessment Report
091823 Geological and Geochemical Report on the Stoddart Property Assessment Report
094323 Prospecting and Hand Pitting on the Seymour Property Assessment Report
094528 Excavator Trenching on the Seymour 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
094477 Prospecting and Hand Pitting on the Seymour Property Assessment Report
094745 2006 Geophysical Assessment Report on the Freegold Mountain Property Assessment Report
096643 2013 Geological and Geochemical Report for the Freegold Mountain Property Assessment Report
2018-2 Bedrock geological map of the Mount Freegold district, Dawson Range Open File (Geological - Bedrock)
Paulter, J. (2006). Evaluation Report on the Freegold Project for Northern Freegold Resources. Available on SEDAR.

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