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Occurrence Details


Occurrence Number
105B 021
Occurrence Name
Silver Hart-TM Zone
Occurrence Type
Hard-rock
Status
Deposit


General Information

Primary Commodities: silver, zinc, lead
Aliases: Bastille, Cmc, Hart, Mid, TM, Silver Hart
Deposit Type(s): Vein Polymetallic Ag-Pb-Zn+/-Au
Location(s): 60.325782 N, -130.732034 W
NTS Mapsheet(s): 105B07
Location Comments: Location from map in 2020 NI43-101 technical report
Hand Samples Available at YGS: No

Capsule

Work History

First staked as Bastille cl (57459) in Aug/48 by Great Northern Exploration Company Ltd, headed by Dr. F.W. Galbraith of the University of Arizona. Restaked as Mid cl 1-29 (Y64349) in Sep/71 by Wolf Lake Joint Venture (Rayrock Mines Ltd, Ashland Oil Inc and Caltor Syndicate), which carried out grid soil sampling and detailed geological mapping in 1972.

Restaked as CMC cl 1-24 (YA56628) in Sep/80 by A.W. Hyde, who trenched later in the year. The CMC cl 25-136 (YA66067) were staked in Jul/81 to surround the occurrence. The claims were optioned to BRX Mining & Petroleum Corp in 1982, which carried out geological mapping, geochemical sampling and drilled 2 holes (197 m) later that year. McDame Project (BRX Mining & Petroleum Ltd, Eldorado Minerals & Petroleum Corp and Highmark Resources Ltd) tied on BRX cl 1-20 (YA68275) to the west in May/82 and carried out geological mapping and geochemical sampling later in the year.

After the first option expired, Hyde performed more trenching in 1983 with T. McCrory & B. Preston before optioning the property to United Greenwood Exploration Ltd & Consolidated Montclerg Mines Ltd late in 1983.

When the option lapsed, the owners trenched again and optioned the property for a third time in Nov/84 to a joint venture between Silver Hart Mines Ltd and Shakwak Exploration Company Ltd. The joint venture added about 500 SH, Sab & Bea cl (YA72267) between Oct/84 and Feb/85 and explored with trenching, 50 drill holes (3,658 m), a 673 m adit and 2 raises, and built a 40 km access road in 1985-86.

Early in 1986, Shakwak sold its interest to Ark La Tex Industries Ltd. Silver Hart drilled 4 holes (609.6 m) in 1987 on the main showing and carried out extensive bulldozer trenching of the occurrence and the surrounding claims. Following a feasibility study in 1988, a $10 million deal was signed with with Morgan-Gundy to put the property into production however a drop in silver prices lead to the project's eventual cancellation. Trenching and environmental reclamation was carried out in July and Aug/92.

The CMC claims were later returned to W. Hyde, B. Preston and T. McCrory (60%, 20% and 20%, respectively) who performed environmental reclamation, road construction and bedrock stripping from June to Aug/93. Hyde carried out magnetometer and EM geophysical surveying in 1999. In Jan/2000, 100% interest in the CMC claims was transferred to Hyde. Hyde continued environmental reclamation work, road construction and bedrock stripping in 2000.

In Feb/2005, Bellevue Capital Corporation acquired a 100% interest in the CMC silver property. A technical report prepared in accordance with National Instrument 43-101 was completed at that time. Bellevue was subsequently reorganized and renamed CMC Metals Ltd.

From 2006 to 2010, CMC completed prospecting, geological mapping, trenching, road work, metallurgical testing and drilled 6 068 m in 95 holes. In 2010 the company complete an updated resource estimate.

The site was relatively dormant from 2011 to 2016.

From 2017 to 2022, the company drilled 8 391 m in 71 holes.

Capsule Geology

The original showing consists of galena in leached gossans which cut Cambrian or older biotite-quartz schist, limy hornfels and calcareous horizons near the margin of the mid Cretaceous Cassiar Batholith. Pyritic zones in the schist contain minor chalcopyrite. Minor scheelite, molybdenite, galena and sphalerite are also present in narrow skarn zones near the intrusive contact. Gossan specimens collected at surface in 1971 gave assays up to 270 g/t Ag, 18.5% Pb and 10.1% Zn.

A silver-rich vein was found about 1.6 km to the west in 1982-84. It strikes 045°, dips steeply southeast and is best developed at the batholith contact, which it offsets about 150 m in a left-handed direction. The vein consists of a wide shear zone containing lenses of galena, tetrahedrite and sphalerite. Three mineralized zones about 1.8 m wide named the TM, FM & SM, have been traced for an aggregate length of 1160 m.

Float with similar mineralogy is reported from two areas to the east that also lie near the batholith contact. A new zone (Meteorite Zone) was discovered in 1986 north and east of the FM Zone. It appears to consist of 3 parallel veins. Chip samples taken along a 21 m strike length averaged 1,187.8 g/t Ag across 1.5 m.

Trenching in 1987 identified numerous other mineralized areas. At the end of 1987, Silver Hart reported reserves of 97,370 tonnes grading 1025.1 g/t Ag.

The 1999 geophysical program outlined 5 anomalous areas that contain one or more conductors and/or magnetic anomalies. Three of the areas displayed evidence of previous trenching and/or surface mineralization and two are new untested targets. Hyde trenched some of the targets the following year but the majority of trenching was reclaimation based. Hyde did not file any assays or rock descriptions and only claimed assessment costs for physical work, i.e. volume of material moved.

A  resource estimate, incorporating the 2005-2009 drilling, was released in a report dated January 14, 2010 by Dahrouge Consultants.The resource is quoted at two cut-off grades, which were determined at a silver price of $8.60/oz.

At a cut-off grade of 600g/t AgEq, the combined resource for the TM, KL and M zones is calculated at 69 500 tonnes grading 555.66g/t Ag, 1.89% Pb and 9.12% Zn for  1.24M oz ( 38.5 Mg) Ag. At a cut-off grade of 900g/t AgEq, the combined resource for the TM and M zones total 27 300 tonnes grading 901.04g/t Ag, 3.21% Pb and 12.79% Zn for approximately 0.9 Moz (28 Mg) Ag.

Location Map

Last Updated: Dec 22, 2022

Work History

Year Work Type Comment
2022 Drilling: Diamond 22 holes, 4,400 m
2021 Drilling: Diamond 19 holes, 2,100 m
2019 Drilling: Diamond 16 holes, 1,048 m
2017 Drilling: Diamond 14 holes, 843 m
2011 Drilling: Diamond 95 holes, 6,068 m
2010 Drilling: Diamond 21 holes, 820 m
2010 Studies: Resource Estimate Dahrouge Geological Consulting Ltd, Jan 2010.
2009 Drilling: Diamond 28 holes, 1,929 m
2008 Drilling: Diamond 16 holes, 1,094 m
2007 Drilling: Diamond 1,500 m
2006 Drilling: Diamond 10 holes, 725 m
2005 Studies: Geotechnical Report written by Bellevue Capital Corporation.
1999 Ground Geophysics: Magnetics Also EM survey.
1993 Development, Surface: Access Road
1993 Development, Surface: Reclamation
1992 Trenching: Mechanical
1992 Development, Surface: Reclamation
1987 Drilling: Diamond Four holes, 609.6 m.
1987 Trenching: Mechanical
1986 Trenching: Mechanical
1986 Drilling: Diamond Fifty holes, 3,658 m.
1985 Development, Surface: Access Road
1985 Development, Underground: Drifting/Raising
1985 Trenching
1983 Trenching
1982 Drilling: Diamond Two holes, 197 m.
1982 Geochemistry: Soil
1982 Geology: Bedrock Mapping
1980 Trenching
1972 Geochemistry: Soil
1972 Geology: Bedrock Mapping

Regional Geology - Terrane

Group: Ancestral North America
Affinity: W Laurentia
Name: Cassiar
Realm: Laurentia


Regional Geology - Bedrock

Supergroup:
Group/Suite: Atan
Formation: Boya
Member:
Terrane: Cassiar
Period Max: Cambrian
Age Max: 542 MA
Period Min: Cambrian
Age Min: 510 MA
Rock Major: argillite/shale/siltstone/quartzite/phyllite
Rock Minor: limestone
Reference: Amakun & Lowey (1987) - YGS OF 1987-1
Geological Unit (1M): lCB
Geological Unit (250K): lCB

Assessment Reports that overlap occurrence

Report Number Year Title Worktypes Holes Drilled Meters Drilled
096832 2015 Assessment Report Describing Ground Surveying, Orthophoto Creation and Contour Generation Orthophoto - Airphotography, Surveying - Other
093727 1993 Evaluation Report Physical Representation Report CMC/GL Quartz Claims All Weather Road - Development, Surface, Environmental Clean-up - Development, Surface, Reclamation - Development, Surface
091992 1987 Hart Silver Property, Yukon Territory, Evaluation Survey Rock - Geochemistry, Soil - Geochemistry, Prospecting - Other, Mechanical - Trenching
091990 1987 Interpretation of Color Aerial Photography for the Hart Silver Property Orthophoto - Airphotography
092034 1983 Report on the CMC Claims Property Evaluation - Other
062137 1982 Qualifying Report on the CMC Claims Property Evaluation - Other
091084 1982 Qualifying Report on the CMC Claims Rock - Geochemistry, Soil - Geochemistry
060883 1972 Nite and Mid Claims Report Geology, Geochemistry, Trenching and Diamond Drilling Diamond - Drilling, Rock - Geochemistry, Silt - Geochemistry 8 458

Related References

Number Title Page(s) Document Type
ARMC007614 Examination notes - CMC claims Miscellaneous Company Documents
ARMC007615 Property exams - CMC claims Report
ARMC007616 Additional sampling - CMC claims Miscellaneous Company Documents
ARMC007617 Map - S2 and FM trench area geology - CMC claims - Edgar Lake area Geoscience Map (Geological - Bedrock)
ARMC007609 Certificate of assay - A8413612-001-A - CMC claims Assays
ARMC007610 Certificate of assay - A8414422-001-A - CMC claims Assays
ARMC007613 Notes - Examination - Jack property Miscellaneous Company Documents
ARMC007611 Certificate of assay - A8412840-001-A - CMC claims Assays
ARMC007612 Notes - Examination - CMC claims Miscellaneous Company Documents
Citations
CMC Metals Ltd., 2021, NI 43-101 Technical Report and Mineral Resource Update on the Silver Hart Property. Dated December 2, 2020. p 92.
Dahrouge Geological Consulting Ltd, Jan 2010. Technical Report on the Silver Hart Property, by n. McCallum and J. Gorham, for CMC Metals Ltd.
Norecol Environmental Consultants Ltd, 1987. Silver Hart project overview report.

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