General Information
Primary Commodities: molybdenum, tungsten, tungsten trioxide
Secondary Commodities: beryl
Aliases: Northern Dancer
Deposit Type(s): Porphyry W
Location(s): 60.005280 N, -131.597780 W
NTS Mapsheet(s): 105B04
Location Comments: .5 Kilometres
Hand Samples Available at YGS: Yes
Capsule
Work History
Mineralization was first noted by the Geological Survey of Canada in the early 1950s but the first claims were staked in Sep/76 as Log cl 1-138 (YA11210) by Bath 1976 Uranium Partnership (W.M. Bath Investments Ltd, Sicintine Mines Ltd and several individuals), which performed limited mapping and sampling in 1976 and formed a new company, Logtung Resources Ltd, to develop the property.
Amax Potash Ltd tied on Top cl 1-54 (YA11472) to the northwest in Oct/76, optioned the Logtung property, built a road, and explored with mapping, geochem and IP surveys, 51 holes (11 628 m), 496 m of decline and drifts, a 15 000 tonne bulk sample and preliminary engineering, metallurgical and environmental studies between 1977 and 1981. Logtung changed its name to Regional Resources Ltd and W.M. Bath Investments changed to Petromin Resources Corporation in 1982 and Amax's interest was transferred to Canamax Resources Inc in 1983.
Canamax dropped its interest in 1986 and the Log claims were transferred back to Logtung Resources in Sep/86. In Dec/92 the Barb and Log claims were transferred to 7188 Yukon Ltd.
In Jun/93, NDU Resources Ltd entered into an option agreement with Regional to obtain a 50% interest in the Yukon portion of the property. The agreement required NDU to evaluate the gold potential of the deposit and surrounding area over a 3 year period. In July and Aug/93, NDU conducted an exploration program which included prospecting, soil geochemical surveys and two diamond drill holes totaling 234 m. NDU dropped its option at the end of 1993.
The Barb and Log claims covering the deposit began to lapse in early 1998. Nordac Resources Ltd staked Dansar cl 1-6 (YB91322) in Jun/98. These claims covered the portion of the deposit located in the Yukon Territory. The company also staked claims in British Columbia to cover the portion of the deposit located in that province. During the summer of 1998 Nordac carried out a few prospecting traverses on the claims and began removing old drums which had been abandoned on the claims. In 2000 the company examined the beryl potential of the property and removed the remaining barrels.
In Mar/2001 Nordac staked Dansar cl 7-14 (YB93166). The company re-organized and changed its name to Strategic Metals Ltd in Jun/2001. Upon acquiring the Logtung property Strategic Metals began digitizing all previous exploration data. In Sep/2001 the company carried out a brief prospecting program to verify previous results. The company also staked Dansar cl 15-23 (YB93172). The digitizing program continued through 2002. In Aug 2003 the company carried out a small prospecting and hand trenching program.
Largo Resources optioned the property in 2006 and performed 3945 m of diamond drilling in 17 holes. A total of 26 holes (8494 m) were completed in 2007 and a total of 38 holes (11 500 m) in 2008. Drilling in 2008 tested the deposit downdip and added infill drilling in order to support an upgrade of the resource calculation for a preafeasbility study.
work history between 2008 and 2011 has not yet been updated.
...
In march 2011, the company released a Preliminary Economic Assessment.
Capsule Geology
The property is located in south-central Yukon near the border with British Columbia. Recent geological mapping completed by geologists employed by the Ancient Pacific Margin NATMAP project; a projected jointly funded by the Geological Survey of Canada, the British Columbia Geological Survey and the Yukon Geology Program shows the area is underlain by mafic to intermediate volcanic and epiclastic rocks assigned to the Klinkit Succession. Recent age dating by Mortensen and Gabites (2002) has resulted in a Pennsylvanian age for the Klinkit Succession. Roots and et al., have recently assigned the Klinkit Succession to the Yukon-Tanana terrane.
The Klinkit Succession is intruded by a Triassic diorite stock flanked by numerous satellite dikes and a mid-Cretaceous monzonite stock accompanied by pegmatitic dike swarms and a slightly younger but apparently comagmatic felsic dike complex. Both ages of intrusions produced extensive hornfels halos and localized skarn horizons. Mineralization is hosted by an extensive, multi-episode vein system that is enriched in several metals, most notably tungsten and molybdenum. The vein system is centred on the felsic dike complex, and approximately 95% of the mineralization occurs within veins and fractures with the remainder found as disseminations within the felsic dike complex and skarn horizons. The veins crosscut all units and are believed to be genetically related to emplacement of the felsic dike complex.
The original mineralized showing found by the GSC consisted of blades of wolframite with purple fluorite, tourmaline, cosalite and beryl in a quartz vein cutting quartz monzonite. The main zone found nearby in 1976 consists of scheelite and molybdenite in a multi-stage stockwork vein system developed in a quartz porphyry plug, and disseminated in a vein stockwork which cuts garnet-diopside skarn and hornfels peripheral to a fluorite-rich quartz monzonite stock which intrudes cherty banded argillite and quartzite of Pennsylvanian age.
Mineralization is controlled by four overprinting stages of veining: (Type 1) quartz-molybdoscheelite veins occurring up to 1.5 km away from the western edge of the monzogranite, but most well developed in calc-silicate rocks near the felsic dike complex at the north flank of the main stock; (Type 2) quartz-pyrite-scheelite proximal to felsic dikes; (3) quartz-moly in and near the felsic dikes; and (4) polymetallic sheeted veins.
Studies by Noble, Spooner & Harris suggest that this deposit has many similarities to classic porphyry Mo deposits and that the skarn minerals are incidental to the W-Mo mineralization, which is almost totally confined to porphyry-style crackle breccia.
The 1993 exploration program evaluated the deposit as a bulk tonnage gold target. The results of the soil geochemical survey were generally low, although four strongly anomalous values ranged up to 273 ppb Au. The chip and rock samples returned low values of gold. The two diamond drill holes were cored in diorite which contained minor pyrrhotite, pyrite, chalcopyrite, scheelite and molybdenite, primarily along fractures. Assay values of the drill core were low for all metals.
The 1998 prospecting program identified beryl in crushed material on the dumps from the underground development and in several narrow quartz veins on the periphery of the deposit. Specimens assayed up to 5.36% BeO, 4.60% WO3 and 0.91% MoS2. In 2000 the company collected a 20 kg composite sample of dump material to determine whether or not the dump contained economic amounts of beryl. Although the dump material was enriched in tungsten and molybdenum, the beryl content was low.
The 2001-2002 digitizing exercise allowed the company to plot all known geochemical results on a common 1:50 000 scale map. The results revealed that an area of strongly anomalous tungsten in soil values lies southwest of the defined deposit. Samples collected within the anomaly but outside of the deposit average 1577 ppm WO3 compared to 240 ppm WO3 from samples collected directly over the deposit. Further analysis of the data identified 5 areas (A-E) hosting sheeted veins and related pegmatite dikes which may host economic quantities of tungsten and/or molybdenum. The bulk of the prospecting and hand trenching was carried out in the vicinity of area C. The best chip sample returned 10.33% WO3, 0.13% MoS2, 1.88% bismuth and 8 ppm beryllium across 65 cm.
The work history between 2008 and 2011 has not yet been updated.
...
A Preliminary Economic Assessment, dated march 2011, was prepared by AMC Mining Consultants for Largo Resources Ltd. The report states that a lower cut-off grade of 0.04% WO3 was more appropriate than the 0.06% WO3 cut-off grade used in the 2009 estimate, considering current metal prices and economic paramaters. The 2011 mineral inventory estimate, reported at a 0.04% WO3 cut-off grade, contains Measured mineral resources of 37.2 million tonnes grading 0.10% WO3 and 0.030% Mo, and Indicated mineral resources of 266.1 million tonnes grading 0.09% WO3 and 0.03% Mo. Inferred mineral resources were estimated to be 241.9 million tonnes grading 0.06% WO3 and 0.02% Mo.The financial projections associated with this preliminary economic assessment employ a mining rate for ore and waste of approximately 30M tpa for 23 years, for a total production of 545.2 Mt. During this time there will be sufficient ore stock piled to run the process plant for another 26 years once mining has stopped.
Mineralization was first noted by the Geological Survey of Canada in the early 1950s but the first claims were staked in Sep/76 as Log cl 1-138 (YA11210) by Bath 1976 Uranium Partnership (W.M. Bath Investments Ltd, Sicintine Mines Ltd and several individuals), which performed limited mapping and sampling in 1976 and formed a new company, Logtung Resources Ltd, to develop the property.
Amax Potash Ltd tied on Top cl 1-54 (YA11472) to the northwest in Oct/76, optioned the Logtung property, built a road, and explored with mapping, geochem and IP surveys, 51 holes (11 628 m), 496 m of decline and drifts, a 15 000 tonne bulk sample and preliminary engineering, metallurgical and environmental studies between 1977 and 1981. Logtung changed its name to Regional Resources Ltd and W.M. Bath Investments changed to Petromin Resources Corporation in 1982 and Amax's interest was transferred to Canamax Resources Inc in 1983.
Canamax dropped its interest in 1986 and the Log claims were transferred back to Logtung Resources in Sep/86. In Dec/92 the Barb and Log claims were transferred to 7188 Yukon Ltd.
In Jun/93, NDU Resources Ltd entered into an option agreement with Regional to obtain a 50% interest in the Yukon portion of the property. The agreement required NDU to evaluate the gold potential of the deposit and surrounding area over a 3 year period. In July and Aug/93, NDU conducted an exploration program which included prospecting, soil geochemical surveys and two diamond drill holes totaling 234 m. NDU dropped its option at the end of 1993.
The Barb and Log claims covering the deposit began to lapse in early 1998. Nordac Resources Ltd staked Dansar cl 1-6 (YB91322) in Jun/98. These claims covered the portion of the deposit located in the Yukon Territory. The company also staked claims in British Columbia to cover the portion of the deposit located in that province. During the summer of 1998 Nordac carried out a few prospecting traverses on the claims and began removing old drums which had been abandoned on the claims. In 2000 the company examined the beryl potential of the property and removed the remaining barrels.
In Mar/2001 Nordac staked Dansar cl 7-14 (YB93166). The company re-organized and changed its name to Strategic Metals Ltd in Jun/2001. Upon acquiring the Logtung property Strategic Metals began digitizing all previous exploration data. In Sep/2001 the company carried out a brief prospecting program to verify previous results. The company also staked Dansar cl 15-23 (YB93172). The digitizing program continued through 2002. In Aug 2003 the company carried out a small prospecting and hand trenching program.
Largo Resources optioned the property in 2006 and performed 3945 m of diamond drilling in 17 holes. A total of 26 holes (8494 m) were completed in 2007 and a total of 38 holes (11 500 m) in 2008. Drilling in 2008 tested the deposit downdip and added infill drilling in order to support an upgrade of the resource calculation for a preafeasbility study.
work history between 2008 and 2011 has not yet been updated.
...
In march 2011, the company released a Preliminary Economic Assessment.
Capsule Geology
The property is located in south-central Yukon near the border with British Columbia. Recent geological mapping completed by geologists employed by the Ancient Pacific Margin NATMAP project; a projected jointly funded by the Geological Survey of Canada, the British Columbia Geological Survey and the Yukon Geology Program shows the area is underlain by mafic to intermediate volcanic and epiclastic rocks assigned to the Klinkit Succession. Recent age dating by Mortensen and Gabites (2002) has resulted in a Pennsylvanian age for the Klinkit Succession. Roots and et al., have recently assigned the Klinkit Succession to the Yukon-Tanana terrane.
The Klinkit Succession is intruded by a Triassic diorite stock flanked by numerous satellite dikes and a mid-Cretaceous monzonite stock accompanied by pegmatitic dike swarms and a slightly younger but apparently comagmatic felsic dike complex. Both ages of intrusions produced extensive hornfels halos and localized skarn horizons. Mineralization is hosted by an extensive, multi-episode vein system that is enriched in several metals, most notably tungsten and molybdenum. The vein system is centred on the felsic dike complex, and approximately 95% of the mineralization occurs within veins and fractures with the remainder found as disseminations within the felsic dike complex and skarn horizons. The veins crosscut all units and are believed to be genetically related to emplacement of the felsic dike complex.
The original mineralized showing found by the GSC consisted of blades of wolframite with purple fluorite, tourmaline, cosalite and beryl in a quartz vein cutting quartz monzonite. The main zone found nearby in 1976 consists of scheelite and molybdenite in a multi-stage stockwork vein system developed in a quartz porphyry plug, and disseminated in a vein stockwork which cuts garnet-diopside skarn and hornfels peripheral to a fluorite-rich quartz monzonite stock which intrudes cherty banded argillite and quartzite of Pennsylvanian age.
Mineralization is controlled by four overprinting stages of veining: (Type 1) quartz-molybdoscheelite veins occurring up to 1.5 km away from the western edge of the monzogranite, but most well developed in calc-silicate rocks near the felsic dike complex at the north flank of the main stock; (Type 2) quartz-pyrite-scheelite proximal to felsic dikes; (3) quartz-moly in and near the felsic dikes; and (4) polymetallic sheeted veins.
Studies by Noble, Spooner & Harris suggest that this deposit has many similarities to classic porphyry Mo deposits and that the skarn minerals are incidental to the W-Mo mineralization, which is almost totally confined to porphyry-style crackle breccia.
The 1993 exploration program evaluated the deposit as a bulk tonnage gold target. The results of the soil geochemical survey were generally low, although four strongly anomalous values ranged up to 273 ppb Au. The chip and rock samples returned low values of gold. The two diamond drill holes were cored in diorite which contained minor pyrrhotite, pyrite, chalcopyrite, scheelite and molybdenite, primarily along fractures. Assay values of the drill core were low for all metals.
The 1998 prospecting program identified beryl in crushed material on the dumps from the underground development and in several narrow quartz veins on the periphery of the deposit. Specimens assayed up to 5.36% BeO, 4.60% WO3 and 0.91% MoS2. In 2000 the company collected a 20 kg composite sample of dump material to determine whether or not the dump contained economic amounts of beryl. Although the dump material was enriched in tungsten and molybdenum, the beryl content was low.
The 2001-2002 digitizing exercise allowed the company to plot all known geochemical results on a common 1:50 000 scale map. The results revealed that an area of strongly anomalous tungsten in soil values lies southwest of the defined deposit. Samples collected within the anomaly but outside of the deposit average 1577 ppm WO3 compared to 240 ppm WO3 from samples collected directly over the deposit. Further analysis of the data identified 5 areas (A-E) hosting sheeted veins and related pegmatite dikes which may host economic quantities of tungsten and/or molybdenum. The bulk of the prospecting and hand trenching was carried out in the vicinity of area C. The best chip sample returned 10.33% WO3, 0.13% MoS2, 1.88% bismuth and 8 ppm beryllium across 65 cm.
The work history between 2008 and 2011 has not yet been updated.
...
A Preliminary Economic Assessment, dated march 2011, was prepared by AMC Mining Consultants for Largo Resources Ltd. The report states that a lower cut-off grade of 0.04% WO3 was more appropriate than the 0.06% WO3 cut-off grade used in the 2009 estimate, considering current metal prices and economic paramaters. The 2011 mineral inventory estimate, reported at a 0.04% WO3 cut-off grade, contains Measured mineral resources of 37.2 million tonnes grading 0.10% WO3 and 0.030% Mo, and Indicated mineral resources of 266.1 million tonnes grading 0.09% WO3 and 0.03% Mo. Inferred mineral resources were estimated to be 241.9 million tonnes grading 0.06% WO3 and 0.02% Mo.The financial projections associated with this preliminary economic assessment employ a mining rate for ore and waste of approximately 30M tpa for 23 years, for a total production of 545.2 Mt. During this time there will be sufficient ore stock piled to run the process plant for another 26 years once mining has stopped.
Location Map
Last Updated: Sep 13, 2018
Work History
| Year | Work Type | Comment |
|---|---|---|
| 2011 | Studies: Preliminary Economic Assessment | Largo Resources PEA, 2011. |
| 2008 | Drilling: Diamond | Thirty-eight holes, 11,500 m. |
| 2007 | Drilling: Diamond | Twenty-six holes, 8,494 m. |
| 2006 | Drilling: Diamond | Seventeen holes, 3,945 m. |
| 2003 | Other: Prospecting | |
| 2003 | Trenching: Hand | |
| 2002 | Pre-existing Data: Data Compilation | |
| 2001 | Other: Prospecting | |
| 2001 | Pre-existing Data: Data Compilation | |
| 2000 | Geochemistry: Rock | Collected 20 kg composite sample from dump piles. |
| 1998 | Other: Prospecting | Nordac carried out prospecting in conjunction with drum removal trips. |
| 1993 | Drilling: Diamond | Two holes, 234 m. |
| 1993 | Geochemistry: Soil | |
| 1993 | Other: Prospecting | |
| 1988 | Lab Work/Physical Studies: Metallurgical Tests | |
| 1981 | Development, Surface: Access Road | |
| 1981 | Studies: Environmental Assessment/Impact | |
| 1980 | Development, Underground: Drifting/Raising | Approximately 496 m of drifting and declines. |
| 1980 | Drilling: Diamond | Eleven holes, 3,135 m. |
| 1980 | Geochemistry: Rock | Approximate 15,000 t bulk sample. |
| 1977 | Drilling: Diamond | Fifty-one holes, 11,628 m. |
| 1977 | Geochemistry: Soil | |
| 1977 | Geology: Bedrock Mapping | |
| 1977 | Ground Geophysics: IP | |
| 1977 | Development, Surface: Access Road | |
| 1976 | Geochemistry: Rock | |
| 1976 | Geology: Bedrock Mapping |
Regional Geology - Terrane
Group: Intermontane
Affinity: W Laurentia
Name: Yukon-Tanana
Realm: peri-Laurentian
Regional Geology - Bedrock
Supergroup:
Group/Suite: Finlayson
Formation:
Member:
Terrane: Yukon-Tanana
Period Max: Devonian
Age Max: 365 MA
Period Min: Carboniferous
Age Min: 345 MA
Rock Major: flows/breccia/tuffs/
Rock Minor:
Reference: Gordey & Stevens (1994) - GSC OF 2886
Geological Unit (1M): DMF
Geological Unit (250K): DMF1
Assessment Reports that overlap occurrence
| Report Number | Year | Title | Worktypes | Holes Drilled | Meters Drilled |
|---|---|---|---|---|---|
| 095322 | 2008 | Exploration on the Northern Dancer Property | Diamond - Drilling, Drill Core - Geochemistry, Water - Geochemistry, Metallurgical Tests - Lab Work/Physical Studies, Environmental Assessment/Impact - Studies, Preliminary Economic Assessment - Studies | 38 | 11509.78 |
| 095012 | 2007 | Assessment Report on Year-2007 Surface Exploration and Diamond Drilling on the Northern Dancer Property | Diamond - Drilling, Diamond - Drilling, Detailed Bedrock Mapping - Geology, Environmental Assessment/Impact - Studies | 52 | 16988 |
| 094774 | 2006 | Assessment Report Describing Diamond Drilling at the Northern Dancer Property | Diamond - Drilling | 17 | 3943.80 |
| 094521 | 2004 | Assessment Report Describing Road Construction and excavator Trenching at the Logtung Property | All Weather Road - Development, Surface, Rock - Geochemistry, Backhoe - Trenching | ||
| 094303 | 2002 | Assessment Report Describing Prospecting and Digital Data Compilation at the Northern Dancer Property | Prospecting - Other, Data Compilation - Pre-existing Data | ||
| 094158 | 1999 | Sampling and Reclamation at the Northern Dancer Property | Environmental Clean-up - Development, Surface, Rock - Geochemistry, Rock - Geochemistry, Soil - Geochemistry | ||
| 093994 | 1998 | Prospecting and Reclamation at the Northern Dancer Property | Environmental Clean-up - Development, Surface, Prospecting - Other | ||
| 093178 | 1994 | Prospecting, Geochemical and Diamond Drilling Report NDU Resources Ltd. Logtung Property | Diamond - Drilling, Diamond - Drilling, Drill Core - Geochemistry, Historical Drill Core - Geochemistry, Rock - Geochemistry, Silt - Geochemistry, Soil - Geochemistry, Soil - Geochemistry, Prospecting - Other | 4 | 468.20 |
| 090661 | 1980 | [Diamond Drill Report on the Logjam Property] | Diamond - Drilling | 3 | 813.20 |
| 091102 | 1979 | [Drill Logs] | Diamond - Drilling | 2 | 561.40 |
| 091101 | 1978 | [Diamond Drilling Report Logtung Property] | Diamond - Drilling | 4 | 903.50 |
| 092843 | 1977 | [Diamond Drilling Report Logtung Property by Amax Minerals Exploration] | Diamond - Drilling, Diamond - Drilling | 10 | 1573.40 |
| 091100 | 1977 | [Drill Logs] | Diamond - Drilling | 5 | 1241.10 |
Related References
| Number | Title | Page(s) | Document Type |
|---|---|---|---|
| ARMC007618 | News release - Notes and and drill plan - Logtung project and Logjam Creek | News Release | |
| YEG1979_80 | Yukon Geology and Exploration 1979-80 | 148-149 | Annual Report |
| YEG1981 | Yukon Exploration and Geology 1981 | 98 | Annual Report |
| MIR1977 | Mineral Industry Report 1977 | 78 | Annual Report |
| MIR1978 | Mineral Industry Report 1978 | 56-57 | Annual Report |
| Citations |
|---|
| AMC Mining Consultants, 2011. Northern Dancer Project, Yukon, Canada, Largo Resources Ltd, Preliminary Economic Assessment, March 28 2011. <http://sedar.com> accessed June 2016. |
| BRAND, A., 2008. Mineralogy, geochemistry, and geochronology of the Northern Dancer tungsten-molybdenum deposit, Yukon and British Columbia. Unpublished M.Sc. Thesis, University of British Columbia, Vancouver, BC, 240 p. |
| CANAMAX RESOURCES INC. 1983. Prospectus Report. |
| DICK, L.A., 1980. A comparative study of the geology, mineralogy, and conditions of formation of contact metasomatic mineral deposits in the northeastern Canadian Cordillera. Unpublished PhD thesis, Queen's University, p. 8, 147-148, 150-156, 411-416. |
| HARRIS, F.R., NOBLE, S.R., AND SPOONER, E.C.T., 1984. The Logtung large tonnage, low grade W (Scheelite)-Mo porphyry deposit. Economic Geology, Aug/84, p. 848-868. |
| LOGJAM RESOURCES LTD, 1979. Annual Report, 1979. |
| MORTENSEN, J.K. and GABITES, J.E., 2002. Lead isotopic constraints on the metallogeny of southern Wolf Lake, southeastern Teslin and northern Jennings River map areas, Yukon and British Columbia: Preliminary results. In: Yukon Exploration and Geology 2001, D.S. Emond, L.H Weston and L.L. Lewis (eds.), Exploration and Geological Services Division, Yukon Region, Indian and Northern Affairs Canada, p. 179-188. |
| NELSON, J.L., ET AL., 2000. Ancient Pacific Margin: A preliminary comparison of potential VMS-hosting successions of the Yukon-Tanana Terrane, from Finlayson Lake district to Northern British Columbia. In: Yukon Exploration and Geology 1999, D.S. Emond and L.H. Weston (eds.), Exploration and Geological Services Division, Yukon, Indian and Northern Affairs Canada, p. 79-86. |
| NOBLE, S.R., et al., 1995. Longtung: A porphyry W-Mo deposit in the southern Yukon. In: Porphyry Deposits of the Northwestern Cordillera of North America, T.G. Schroeter (ed.), CIM Special Volume 46. |
| POOLE, W.H., 1956. Geology of the Cassiar Mountains. Unpublished Ph.D. Thesis, Princeton University, p. 179. |
| REGIONAL RESOURCES LTD, 1985. Annual Report. |
| ROOTS, C.F. et al., 2000. Revision mapping of the Yukon-Tanana and equivalent terranes in northern British Columbia and southern Yukon Territory between 1310 and 1320W. Geological Survey of Canada, Current Research 2000-A4, 10 p. |
