Overview and Mineral Resource Estimate
The Pine Point lead-zinc project has a storied history, having been first discovered in 1898 by prospectors heading to the Klondike gold rush. Cominco Ltd. began exploration at Pine Point in 1929, with test-pitting, drilling and shaft sinking. In 1948, Cominco began major exploration work, using the Mississippi-Valley-type model to guide exploration. In the early 1960s, Cominco advanced the project to construction which included a railroad, hydro-electric dam and a town where up to 2000 people could live.
Cominco commenced large-scale mine production in 1964 on the basis of 21.5 million tons averaging 7.2% zinc and 4% lead (1,2). The mine eventually ramped up to a production rate of 10,000 tons per day. The “Pine Point Mine” was actually an assemblage of 50 separate open pits and two underground deposits, lying along a 60-km trend. Some 64 million tonnes grading 7.0% zinc and 3.1% lead (1,3) were mined between 1964 and 1987. A decision was made to close the mine in 1987. About 90 deposits in total were discovered by Cominco and several others were discovered west of the Buffalo River by Westmin Resources Ltd. Previous drilling on the property totals approximately 1.3 million metres in 18,422 holes by Cominco, Westmin and Tamerlane Ventures Inc.
Osisko Metals acquired the project in February 2018 and reported an Inferred Mineral Resource estimate of 38.4 Mt grading 4.58% zinc and 1.85% lead (6.58% ZnEq) on December 6, 2018 (4).
The project is located on the south shore of Great Slave Lake in the Northwest Territories, and is accessible directly and year-round by an all-weather highway from Hay River, the economic “Hub of the North”. The project is comprised of mineral claims and mineral leases covering an area of 22,213 hectares containing key stratigraphy that hosts zinc and lead mineralization. The center of the property is located 96 km east of Hay River that has rail transportation and loadout options as well as other available services. On-site infrastructure consists of approximately 100km of intact haulage roads that link the mineralized zones and an active electrical substation located in the middle of the property that previously serviced mine and mill operations.
2018 Mineral Resource Estimate
The company has reported Inferred Mineral Resources of:
38.4 Mt grading 4.58% zinc and 1.85% lead (6.58% ZnEq)(4)
This 2018 MRE is based on application of open pit parameters and using a Zn equivalent cut-off grade varying from 1.7% to 2.0% depending on pit location and metallurgical parameters. The pit-constrained resource is based on optimized pit shells using a zinc price of US$1.10/lb and a lead price of US$0.90/lb. The 2018 MRE is divided into five geographic zones and incorporates 42 new pits and 2 historical pit expansions (see 2018 MRE map). At the deposit scale, the grade and tonnage show little variability at lower cut-off grades.
The 2018 MRE (effective date: November 14, 2018,) was prepared by Pierre-Luc Richard, P. Geo., an independent Qualified Person at BBA Inc. (See Technical Report dated January 23, 2019).
The 2018 MRE used all available information. The drill hole database includes 18,542 surface drill holes of which 6,880 intercepted mineralization. This includes 318 infill drill holes (23,751 m) completed by Osisko Metals with the remainder comprised of Cominco Ltd.’s historical drill holes, the use of which was validated by a drill hole collar survey and a partial core resampling program.
The Company estimates that the 2018 MRE equates to contained metals of 3.9 Blbs. of zinc and 1.6 Blbs. of lead.
1.The Company is reporting the historical resources for reference purposes only. These resources were mined and fall under past production reported by Rhodes et al. (1984).
2. Giroux and McCartney (2001).
3. Rhodes et al. (1984), conversion tons to tonnes in Hannington (2007).
4. These mineral resources are not mineral reserves as they do not have demonstrated economic viability. The quantity and grade of reported Inferred resources in this MRE are uncertain in nature and there has been insufficient exploration to define these Inferred Mineral Resources as Indicated or Measured. Resources are presented as undiluted and in situ for an open-pit scenario and are considered to have reasonable prospects for economic extraction. The cut-off grade used for the Mineral Resource Estimate ranges from 1.70% to 2.00% equivalent zinc. The reason for the cut-off grade variation is due to the fact that different haulage costs are applied depending on the distance of the deposit to the assumed mill site. It should be noted that no mill is currently present on the Property, and that mill transport distances to the mill were estimated based on the most likely location where a mill could potentially be built if the project moves forward. Additionally, different mine dewatering costs were used for several of the deposits and lower mill recoveries were used for the N-204 deposit. Zinc equivalency percentages are calculated using metal prices, forecasted metal recoveries, concentrate grades, transport costs, smelter payable metals and charges.