Mineral Roundup in the Northwest Territories
Last updated 3/29/2009 at Noon
The Northwest Territories has four operating mines: three diamond producers and one long-running tungsten operation. Exploration and development activity was brisk in 2008 with the most advanced projects located in the Slave Province. Here's a look at mining companies active during 2008 in the Northwest Territories:
BHP Billiton Diamonds Inc. (80 percent) and partners C. Fipke (10 percent) and S. Blusson (10 percent) produced about 3.5 million carats of rough diamonds at the Ekati diamond mine in 2008, making the third consecutive year it has averaged that level of output.
Located about 310 kilometers, or 192 miles, northeast of Yellowknife and 200 kilometers, or 124 miles, south of the Arctic Circle in the Northwest Territories, Ekati is Canada's first diamond mine.
To date, 156 kimberlite pipes have been discovered on Ekati's claim block, and mine operations move from open-pit to underground mining.
Mining continues in the Fox and Beartooth open pits and underground in the Panda and more recently, Koala pipe, from which BHP expects to recover 9.8 million carats of high-quality diamonds over 11 years.
In the Ekati core zone, BHP Billiton and partners also completed reverse circulation drilling and delineation diamond drilling on the deep portions of the Misery pipe.
Rio Tinto subsidiary Diavik Diamond Mines Inc. (60 percent), and Harry Winston Diamond Corp. (40 percent), owners of the Diavik diamond mine reported 6.628 million carats for three quarters of production in 2008 and on-going progress on the venture's current mine plan to begin underground mining in 2009 that will continue beyond 2020.
Open pit mining at Diavik is expected to cease by 2016.
Diavik is located 300 kilometers, or 186 miles, northeast of Yellowknife, and is Canada's second diamond mine.
Crews mined from both ore bodies contained in the ever deepening and maturing A154 open pit during the nine months that ended Sept. 30 as well as the new, adjacent open pit.
Diavik's third ore body, the A418 kimberlite pipe is coming into its own as a producer.
For underground mining to begin, about 20 kilometers, or 12.4 miles, of new underground development and related surface infrastructure costing US$ 787 million will be required.
Diavik Diamond Mines also took a bulk sample from the A21 kimberlite pipe using large-diameter, reverse circulation drilling.
Diavik Diamond completed 7,100 meters of exploration and delineation core drilling on its lease block around the Diavik mine and discovered one new kimberlite.
DeBeers Canada Inc. officially opened the Snap Lake Mine, Canada's first completely underground diamond mine, in July.
The Snap Lake deposit, located 220 kilometers, or about 137 miles, northeast of Yellowknife, has an indicated resource of 1.4 million metric tons and an inferred resource of 25 million metric tons, with a recoverable grade of 1.2 carats per metric ton.
The mine is expected to produce an average of 1.4 million carats of diamonds annually for more than 20 years.
In February, just seven months after startup, DeBeers cut its work force at Snap Lake by 128 employees, or 22 percent, and some 90 contractors, citing poor economic conditions worldwide and the need to operate a sustainable business in 2009.
North American Tungsten, owner and operator of the Cantung Mine in southern Northwest Territories about 300 kilometers northeast of Watson Lake, B.C. and near the Yukon Territory border.
The company is a longtime producer of tungsten concentrate from open pit and underground mines at Cantung and is considered the largest producer of the strategic metal in the West.
In 2008, N.A. Tungsten logged another year of solid output at Cantung, though the performance lagged 2007 levels.
Net production totaled 272,483 metric tonne units with an average grade of 1.03 percent tungsten concentrate and recovery of 73.5 percent, compared with 286,031 MTUs in 2007, grading 1.16 percent WO3 and 74.1 percent recovery.
Sales revenue slipped by C$3.2 million to C$56 million last year, and the company posted a loss for fiscal 2008 of C$11.7 million, down from C$1.2 million a year earlier.
One MTU equals 22.04 lbs. Vancouver, B.C.-based N.A. Tungsten also joined two other companies in forming a new venture, Tundra Diversified Industries LLC, to produce and market proprietary commercial tungsten products manufactured from the tungsten concentrate produced at its mining operation.
On-going definition and exploration drilling at the mine resulted in discovery and expansion of more high-grade mineralization at the lower levels of the West Extension zone of the mine.
Meanwhile, infill drilling on the Mactung deposit 160 kilometers, or 99 miles, to the north continued.
In February, the company announced completion of a bankable feasibility study for the Mactung deposit based on an initial 2,000-tpd underground mine with an 11-year mine life and the potential for expansion to open pit operation that could extend production by another 17 years.
Mactung is estimated to contain an indicated resource of 33 million metric tons grading 0.88 percent tungsten concentrate with an additional 11.8 million metric tons grading 0.78 percent WO3 in the inferred resource category.
Advanced development projects
Canadian Zinc Corp. continued to advance its Prairie Creek zinc-lead-silver project on many fronts toward production in 2008.
The project is located in an environmentally sensitive remote area in the Mackenzie Mountains, within the watershed of the South Nahanni River, about 170 kilometers by winter access road from the Liard Highway.
It entered the environmental assessment stage in May when Canadian Zinc began to apply for the major operating permits needed for mining.
A pre-feasibility study is under way that focuses on detailed process design, underground tailings disposal and mine planning and scheduling.
Canadian Zinc envisions operating at 600 tpd to 1,200 tpd year-round, underground using existing infrastructure and facilities built in the 1980s that will be upgraded and enhanced to meet current environmental standards, along with improvements such as a new fuel-efficient low-emission power generation plant.
The current plan calls for a mine life of 10-14 years with 220 full-time jobs.
In December, Canadian Zinc decided to preserve cash in light of the recent economic downturn by terminating all activity at the Prairie Creek Mine site for the winter and is expected to maintain a minimal presence indefinitely at Prairie Creek beginning in April or May.
Located on Kennady Lake some 300 kilometers, or 186 miles, northeast of Yellowknife, the Gahcho Kué Project consists of a cluster of three primary kimberlites with an indicated resource of about 14.4 million metric tons grading 1.64 carats per metric ton (about 23.6 million carats) and an inferred resource of about 17 million metric tons grading at 1.35 c/t (about 22.9 million carats).
It is considered one of the largest diamond deposits under development worldwide.
In 2008, a bulk sampling program of the deposit's Tuzo kimberlite was undertaken to recover about 1,500 carats.
The first 715.6 metric tons of kimberlite yielded 2.16 carats per metric ton and a high-quality 25.13-carat diamond.
The data from the carats taken in the bulk sampling, along with nearly 600 carats recovered from Tuzo in earlier years are being incorporated into a diamond revenue model for the pipe.
Work in 2009 is focused on three areas of baseline data collection - caribou, hydrology and upland birds.
Water quality monitoring for the cuttings containment facility and remediation work for continual improvements to the site also will continue in 2009.
De Beers also told regulators last fall that it will delay submitting an environmental impact statement for the project until late 2009.
Fortune Minerals Inc. continued to advance its Nico cobalt-gold-bismuth project 160 kilometers, or 99 miles, northwest of Yellowknife in 2008.
In May, Fortune Minerals updated a bankable feasibility study prepared for Nico in January 2007 that calculated proven and probable reserves of 21.8 million metric tons suitable for a 15-year mine life with a production rate of 4,000 metric tons of ore per day.
The deposit was estimated to contain 760,000 ounces of gold, 61 million pounds of cobalt and 77 million pounds of bismuth.
Using new flotation metallurgical recoveries, the updated study reported enhanced economics for the project.
In early 2009, Fortune reported a 16 percent increase in the proposed mine's planned production rate due to reconfiguring mills that the company purchased and moved, along with other equipment, from the Golden Giant Mine in Hemlo, Ont.
Fortune also said a pilot plant successfully proved the processing of ores from Nico into high value metal products: cobalt and bismuth cathode, gold doré and copper cement.
Tamerlane Ventures Inc. completed confirmation drilling for a feasibility study of the Pine Point lead-zinc deposit, located on the south side of the Great Slave Lake 129 kilometers, or 80 miles, south of Yellowknife and 80 kilometers, or 50 miles, east of Hay River in 2008.
The historic Pine Point Mine, the largest and most profitable zinc-lead mine in Canadian history, extracted more than 64,259,570 metric tons of ore at a grade of 7.0 percent zinc and 3.1 percent lead between 1964 and 1987.
A new proven and probable reserve estimate for the property is 7.8 million metric tons grading 6.16 percent zinc and 3.01 percent lead; measured and indicated resources are 8 million metric tons grading 2.26 percent zinc and 1.13 percent lead.
Tamerlane obtained permits to begin mine construction, focusing on the 1-million-metric-ton R190 deposit which has an average grade of 11.16 percent zinc and 5.49 percent lead, and drilled 5,317 meters to test 16 other previously known deposits in the area.
The junior also secured a 10-year supply of low-cost hydroelectric power for the Pine Point project.
Advanced exploration projects
Alberta Star Development Corp. looked east of Great Bear Lake in 2008, drilling 2,348 meters over 17 holes in its search for copper, gold and uranium at its Eldorado and Contact Lake projects. The Eldorado-Contact Lake claim block is located five kilometers, or 3 miles, southeast of Port Radium. The drill-hole program followed up 2007 drilling on the Skinny Lake and K-2 target areas and tested three new target areas, K-4, Long Bay, and Gossan Island. Highlights of assay results include a 40.5-meter intercept grading 0.361 percent copper and 2.83 g/t silver in the K2 iron oxide-copper-gold target.
Arctic Star Diamond Corp. reported a new nickel sulphide discovery near Credit Lake located 36 kilometers, or 22 miles, west of the Ekati diamond mine.
The junior tested the magmatic nickel-copper-cobalt-platinum group elements, massive sulfide mineralization with 1,650 meters of drilling over 15 holes, of which 14 intersected multiple mineralized intervals per hole totaling up to 25 meters of massive, net-textured and disseminated mineralization and up to 4.95 meters of massive sulfide.
Highlights of the program included a 5.1-meter intercept yielding 1.73 percent nickel, 1.75 percent copper and 0.17 percent cobalt.
Arctic Star said the discovery has drill-proven sulfide intercepts over 450 meters strike length.
Targets in the zone were developed from reconnaissance mapping, sampling and airborne geophysics.
Avalon Rare Earth Metals Inc., formerly Avalon Ventures Inc., followed up in 2008 on encouraging exploration results from 2007 at its Thor Lake Rare Earth Elements Project in the Mackenzie Mining District of Northwest Territories in 2008.
The 10,449-acre, or 4,249-hectare, property is located about 5 kilometers, or 3 miles, north of the Hearne Channel of Great Slave Lake and about 100 kilometers, or 60 miles, southeast of Yellowknife.
Avalon completed a C$5.4 million, 69-hole drill program covering 14,129 meters in the Lake Zone deposit to define sufficient indicated and inferred resources on which to base a pre-feasibility-level analysis of the project.
In February, Avalon reported more encouraging results in a new REE resources estimate for the Lake Zone deposit, noting the presence of enough high-grade mineralization to warrant initiation of a pre-feasibility study of the Thor Lake REE project later in 2009.
Diamond Exploration Inc., formerly Patrician Diamonds Inc., drilled the Hillside kimberlite in its Doctor Lake Project about 60 kilometers, or 37 miles, north of Norman Wells in 2008 and obtained microdiamonds from a 173-kilogram sample. The results confirm that Hillside is diamond-bearing and suggest that other kimberlite targets in the project area may have good diamond potential. Hillside is the first reported diamond-bearing kimberlite discovered in the region west of Great Bear Lake.
Diamondex Resources Ltd., a spinoff from Winspear Diamonds Ltd. before De Beers Canada Mining Inc. purchased Winspear and Aber Diamond's interest in the Snap Lake diamond deposit in 2000 for C$480 million, has since been focused on finding another large diamond deposit in Northwest Territories.
In 2008, Diamondex followed up on a 2007 exploration program at its Lena West Project, which encompasses 3.35 million acres, and is centered about 900 kilometers, or 650 miles, northwest of Yellowknife.
Since 2002, Diamondex has spent C$18.5 million on exploration at Lena West, taking 5,000 heavy mineral samples and 152,500 line-kilometers of airborne magnetics and completing 1,396 meters of diamond drilling.
GGL Diamond Corp. drilled for nickel in two locations in the Providence greenstone belt. The junior intersected massive to stringer pyrrhotite-pyrite mineralization in six of nine drill holes over apparent true widths of between 1 and 13 meters. It also conducted airborne geophysics and prospecting. GGL also said 114 target areas were visited and 1,165 samples were taken. Following the 2008 field exploration season, gold and VMS discoveries at the PGB property are ready for the next stage of exploration. Nickel also remains a viable target on PGB, the junior added.
New Nadina Explorations (57 percent) and partners Archon Minerals (20 percent) and Chris and Jeanne Jennings (22 percent) completed 4,223 meters of drilling at their Monument Project due south of the Ekati leases, discovered four new kimberlite pipes (Bling, Trio, Gemini and Sparky) and delineated three previously known pipes.
Macro-diamonds were recovered from Trio (16 of 106 stones from 1,015 kilograms); Bling (one of 28 stones from 38 kilograms); Gemini (eight of 147 stones from 348 kilograms); Sparky (15 of 207 stones from 412 kilograms); DD39 (three of 91 stones from 192 kilograms); and Sonja (three of 100 stones from 198 kilograms.
Six micro-diamonds also were recovered from 18 kilograms in the Genie pipe.
In all, New Nadina and its partners have diamond counts from nine kimberlites, and a total of 5.18 metric tons of kimberlite has so far yielded 56 diamonds larger than a 0.85-millimetre mesh.
Those stones likely weigh about 1.7 carats, suggesting a sample grade of about one-third of a carat per metric ton.
New Nadina Explorations Ltd. also said in November it would like to take a larger mini-bulk sample from Monument this spring.
Sanatana Diamonds Inc. and Kennecott Canada Exploration discovered a new kimberlite, Dharma Uttar, on the Greenhorn Project in the northwestern NWT. The companies drilled six holes in the kimberlite.
Thirteen additional magnetic anomalies were drilled using a helicopter-portable, reverse-circulation rig.
The Dharma Uttar kimberlite occurs about 50 meters north of Sanatana's Dharma discovery in 2007 and the two features appear to form a kimberlite complex of dykes, sills and pipes.
A 449-kilogram sample of the Dharma Uttar pipe yielded eight stones larger than 0.85 millimeters.
The companies also completed ground geophysics in 2008 and Sanatana drilled 1,200 meters on 12 targets, but no kimberlites were intersected.
Snowfield Development Corp. and Dave Smith processed 100 metric tons in 2008 of the 500-metric-ton bulk sample of the Mud Lake kimberlite that it collected a year earlier in its Ticho Project, located on the north shore of Great Slave Lake about 55 kilometers, or 34 miles, southeast of Yellowknife. Three macro-diamonds were recovered. Two more diamonds larger than 0.4 millimeters were recovered from 154 kilograms of kimberlite core during 2008 delineation drilling on the sill extension. Snowfield and its partners also completed 2,141 meters of exploration drilling east of the Mud Lake kimberlite.
Strongbow Exploration Inc. continued to explore for nickel and copper at Thye Lake on the Nickel King property in 2008, drilling 44 holes covering 9,200 meters.
Nickel King is located about 550 kilometers, or 341 miles, southeast of Yellowknife.
As a result, the Main Zone has been extended by another 400 meters, bringing its total strike length to more than 2,600 meters.
Notable intercepts included 12.5 meters grading 1.07 percent nickel, 0.26 percent copper and 0.041 percent cobalt and 9 meters, grading 1.16 percent nickel, 0.24 percent copper and 0.051 percent cobalt.
Airborne geophysics and lake sediment sampling also were completed to the south.
An NI 43-101 resource estimate for Nickel King, reported in February, included an indicated resource of 11.11 million metric tons grading 0.40 percent nickel, 0.10 copper and 0.018 cobalt, and an inferred resource of 33.06 million metric tons grading 0.36 percent nickel, 0.09 percent copper and 0.017 percent cobalt.
Tyhee Development Corp. continued to advance its Yellowknife Gold Project 90 kilometers, or 66 miles, north of the city of Yellowknife in 2008.
Tyhee reported measured and indicated resources for its Ormsby, Nicholas Lake and Bruce Lake zones of 14.4 million metric tons grading 3.43 grams per metric ton gold.
Drilling continued in all three zones.
Tyhee submitted a project description report to the Mackenzie Valley Land and Water Board outlining a combined open-pit and underground operation planned at 3,000 tpd to recover an average of 163,500 ounces of gold annually for the first seven years.
Tyhee also holds several other properties stretching between the Giant Mine property and the Yellowknife project and drilled the BigSky zone north of Dwyer Lake.
The 35-hole drill program extended the mineralized segment of WK shear to a strike length of 370 meters.
At Clan Lake, drilling extended the Main zone by 30 meters, including intersections of 134.9 meters grading 0.81 g/t gold.
Uravan Minerals Inc. and Cameco Corp. explored for uranium in the Thelon Basin area in 2008, collecting 2,500 soil and 2,500 vegetation samples over the G, F, H, T and Edge-conductive trends of the Northern Boomerang Project.
Located about 488 kilometers, or 300 miles, east of Yellowknife along the southwestern margin of the Thelon Basin, Boomerang is a joint venture in which Cameco has an option to earn 60 percent interest in the property.
In September, the Mackenzie Valley Environmental Impact Review Board recommended that the Boomerang Project be rejected without an environmental impact review, citing "likely significant adverse cultural impacts on the aboriginal peoples who value the Upper Thelon River Basin." Uravan said the review board's decision effectively froze its assets and sterilized its sunk cost in the Boomerang Project.
Uranium North Resources Corp. prospected and collected samples in 2008 for lithogeochemistry on its Hepburn property while exploring for uranium in the Proterozoic Hornby Bay Basin east of Great Bear Lake. The junior had collected 64 rock samples and conducted 21,000 line-kilometers of airborne geophysics on Hepburn in 2007 and completed detailed ground surveys over several targets on its Thelon UNR Property, as well as 4,250 line-kilometers of airborne geophysics surveys.
Early stage exploration projects
Almaden Minerals Ltd. and partners collected till samples at their ATW diamond property using sonic overburden drilling and defined a target beneath Mackay Lake. This work, plus reinterpretation of past data, resulted in plans to conduct a diamond drill program in 2009. The project is located about 29 kilometers, or 18 miles, south of the Diavik diamond mine.
Aurora Resources Inc. conducted soil geochemistry tests in 2008 on its Wrigley zinc-lead property located on the north end of the Camsell Range near the Mackenzie River in the Northwest Territories.
Consolidated Global Diamond drilled 850 meters into fine-grained pyroclastic kimberlitic rock at Courageous Lake. This material yielded micro diamonds.
Eagle Plains Resources and Teck explored for zinc and lead in the Mackenzie Mountains by conducting geochemical and ground geophysical surveys.
Freeport-McMoRan Copper and Gold and Kaska Minerals explored for sedimentary-hosted copper deposits with silt sampling on their Keele River property west of Norman Wells.
Great Bear Uranium and Hillcrest Resources conducted an airborne magnetics, radiometric and VLF geophysical survey over their Thelon uranium project in the Thelon Basin area.
Great Northern Mining and Exploration followed up on till samples taken in 2007 with drilling and prospecting in 2008 for nickel and platinum group elements on claims just east of the Minto Inlier property on Victoria Island.
Olivut Resources Ltd. drilled 23 holes, 16 of which intersected kimberlite in the HOAM project areas, both near Fort Simpson and along the southern edge of Great Bear Lake. The junior discovered eight new kimberlite bodies and completed airborne magnetic and ground gravity surveys. The junior said many priority targets remain untested at HOAM and will be drilled in following programs.
Shear Minerals Ltd. and partners drilled 12 priority geophysical targets at Afridi Lake including the previously discovered DA1 and DA2 diamondiferous kimberlite pipes. About 175 meters of the DA1 pipe was intersected in the first drill hole. They also completed ground geophysical surveys on the property.
Viking Gold Exploration drilled 2,689 meters over 12 holes on the Morris Lake gold property just south of the former Discovery gold mine. Ten of the 12 holes intersected the mineralized Viking Zone, extending it to a vertical depth of 210 meters.
Sources: Northwest Territories Geoscience and companies listed.