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Occurrence Details


Occurrence Number
115I 039
Occurrence Name
Com
Occurrence Type
Hard-rock
Status
Anomaly


General Information

Secondary Commodities: copper, tungsten, fluorite
Aliases: Freegold
Deposit Type(s): Porphyry Cu-Mo-Au
Location(s): 62.359170 N, -137.389170 W
NTS Mapsheet(s): 115I06
Location Comments: 1 Kilometres
Hand Samples Available at YGS: No

Capsule

Work History

Staked as Com cl (Y38245) in September 1969 by Cominco, which conducted soil sampling in 1970. The Roy and Tye cl (Y50930) were staked immediately to the southwest in March 1970 by Eagle Bay ML. Re-staked in December 1974 as Roc cl (Y91852) by Klotassin JV (Newconex Can EL, Marietta Res Int L, and Molybdenum Corp of America), which conducted mapping, geochemical sampling, a ground magnetic survey and limited bulldozer trenching in 1975; and a ground magnetic survey in 1976.

Archer, Cathro & Associates Ltd. performed bedrock mapping, as well as soil and rock geochemistry in 1985.

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 (Allan & Friend, 2018; AR 090087), including:
1. Early Jurassic monzonite to syenite plutonic suites;
2. Mid-Cretaceous Mount Nansen Suite andesite and rhyolite tuff-breccia;
3. Mid-Cretaceous Whitehorse granodiorite;
4. Late Cretaceous Carmacks rhyodacites; and,
5. Quartz feldspar and feldspar hornblende porphyry dykes and plugs.

Mineralization & Results

Small copper and molybdenum soil anomalies were outlined along the southwest side of the valley floor on the Com claims. Mapping of the rock chips collected during soil sampling delineated several small porphyry stocks and related dyke swarms, with a trace of malachite, that appear to be the source of the anomaly. Minor banded and disseminated fluorite was found in quartz float along Big Creek and one specimen was found to contain abundant scheelite.

Location Map

Last Updated: Dec 16, 2020

Work History

Year Work Type Comment
1985 Geochemistry: Rock
1985 Geochemistry: Soil
1985 Geology: Bedrock Mapping
1976 Ground Geophysics: Magnetics
1975 Geology: Bedrock Mapping
1975 Ground Geophysics: Magnetics
1975 Trenching: Mechanical
1970 Geochemistry: Soil

Regional Geology - Terrane

Group: Intermontane
Affinity: W Laurentia
Name: Yukon-Tanana
Realm: peri-Laurentian


Regional Geology - Bedrock

Supergroup:
Group/Suite: Long Lake?
Formation:
Member:
Terrane:
Period Max: Jurassic
Age Max: 188 MA
Period Min: Jurassic
Age Min: 183 MA
Rock Major: monzonite
Rock Minor:
Reference: Allan & Friend (2018) - YGS OF 2018-2
Geological Unit (1M): EJL
Geological Unit (250K): EJyL

Assessment Reports that overlap occurrence

Report Number Year Title Worktypes Holes Drilled Meters Drilled
094745 2006 2006 Geophysical Assessment Report on the Freegold Mountain Property Electromagnetic Airborne Geophysics, Magnetic Airborne Geophysics
094256 2001 Diamond Drilling, Excavator Trenching, and Geophysical Surveys on the Golden Revenue Property Diamond Drilling, Drill Core Geochemistry, IP Ground Geophysics, Prospecting Other, Mechanical Trenching 6 1202
094102 1999 Geological Mapping, Prospecting, Soil Geochemistry, Hand Trenching, and Ground Magnetic Surveys on the Golden Revenue Property Soil Geochemistry, Detailed Bedrock Mapping Geology, Magnetics Ground Geophysics, Prospecting Other, Hand Trenching
091804 1985 Geological and Geochemical Report on the NUCLEUS Property Rock Geochemistry, Soil Geochemistry, Bedrock Mapping Geology, Property Evaluation Other, Prospecting Other, Mechanical Trenching
090167 1976 Geological Mapping, Geochemical and Magnetometer Surveys May-August, 1976 Skunk 1-75 Mineral Claims Rock Geochemistry, Soil Geochemistry, Regional Bedrock Mapping Geology, Magnetics Ground Geophysics, Line Cutting Other
090087 1975 Geological Mapping, Geochemical and Magnetometer Surveys - Big Creek West, Big Creek East, Bow Creek Properties Soil Geochemistry, Regional Bedrock Mapping Geology, Magnetics Ground Geophysics, Line Cutting Other, Prospecting Other, Surveying Other
060200 1970 Report on the Geophysical and Geochemical Surveys Ram and Bow Claim Groups Electromagnetic Airborne Geophysics, Magnetic Airborne Geophysics, Rock Geochemistry, Soil Geochemistry
060606 1969 Geochemical Report on the Com Group East and Com Group West Mineral Claims Soil Geochemistry

Related References

Number Title Page(s) Document Type
ARMC016627 Land and disposition and mineral deposits chart - Freegold - Big Creek area Geoscience Map (General)
ARMC012940 Location plan of Com 1 to 101 mineral claims - Job 379 Geoscience Map (General)
ARMC016626 Geology and mineralization chart - Freegold - Big Creek area Geoscience Map (Geological - Bedrock)
060606 Geochemical Report on the Com Group East and Com Group West Mineral Claims Assessment Report
090167 Geological Mapping, Geochemical and Magnetometer Surveys May-August, 1976 Skunk 1-75 Mineral Claims Assessment Report
091804 Geological and Geochemical Report on the NUCLEUS Property Assessment Report
090087 Geological Mapping, Geochemical and Magnetometer Surveys - Big Creek West, Big Creek East, Bow Creek Properties 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
2018-2 Bedrock geological map of the Mount Freegold district, Dawson Range Open File (Geological - Bedrock)
Citations

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