The TBN project is situated approximately 50km northeast of the city of Thunder Bay, within the Thunder Bay Mining Division, in Ontario, Canada. The project boasts excellent infrastructure and is accessible using provincial highways and forest access roads which cross overtop both deposits.
Figure 1: Project Location
The TBN project is located in a region with several operating mines which include the Lac Des Iles mine owned by Impala Platinum Holdings and the Eagle mine owned by Lundin Mining.
Figure 2: Project Location & Claim Block
Clean Air Metals has completed the amalgamation of the Thunder Bay North Critical Minerals (TBN) project area and owns 100% of the Property. The TBN project comprises of three historical projects:
The amalgamation of the Thunder Bay North Critical Minerals project was accomplished through the 2020 execution of a definitive agreement with Benton Resources for the rights to purchase the Thunder Bay North Property from Panoramic Resources Ltd. for C$9 million and the purchase of the Escape Lake Project from Rio Tinto for C$6 million through staged payments. Finalization occurred in December 2022 with last staged payment to Panoramic Resources.
Figure 3: Claim Block & Thunder Bay North Intrusive Complex
The Thunder Bay North Intrusive Complex is part of the 1.1 billion year old Midcontinental Rift (MCR) that was centred on the Lake Superior area. Intrusive and extrusive volcanic activity was extensive in the area leading to many of the landscapes around Thunder Bay and the greater Lake Superior basin. Rift settings are well known to host orthomagmatic mineralization (Ni-Cu-Pt-Pd-Co) with the Noril’sk-Talnakh deposits of Northern Russia the type example. The Lake Superior MCR is no exception with active Ni-Cu-PGE mining occurring at the Eagle Mine in Michigan, and advancing projects at Tamarack, Duluth, Marathon (Fig. 1).
The TBN project encompasses the Thunder Bay North Intrusive Complex (TBNIC) which comprises a number intrusions of the same age and similar rock types, with a common parental magma source. These include the Current intrusion, Escape Intrusion, Lone Island North, Lone Island South, 025-intrusion and a number of smaller sills and dykes. Platinum, palladium, nickel and copper mineralization or anomalism is identified in all the intrusions with the Current and Escape intrusions being the initial discoveries, primary focus of exploration work and host the 43-101 compliant mineral resources .
The Current intrusion, also known as chonolith based on its morphology of a sinuous magma tube, has a strike and plunge extent of greater then 5km. Mineralization is identified along its entirety and remains open at depth to the south east. Exploration work has focused on the shallower mineralization (<500m) and defined a number of mineralized zones that contribute to the indicated mineral resource completed by SLR Consulting in 2023. These zones from north to south comprise Upper Current, Lower Current, Bridge, Cloud and Beaver Zones. Continuing down plunge is the 437-zone and SEA area which is classified as inferred material.
The Escape intrusion located approximately 3km to the west is also a chonolith with a drill defined strike extent of ~4km with an interpreted 2.5km untested plunge extension as defined by a magnetic anomaly. Mineralization occurs along the entire drill defined strike extent with Steepledge, Escape North, Escape South and High Grade Zone (HGZ) domains defined and the latter three classified as indicated resources.
Figure 4: Mineralized Zones
Anomalous mineralization is identified within Lone Island North (3.25m at 0.76g/t Pt+Pd from 63m in drill hole LIL08-02): Lones Island South (0.75m at 0.55g/t Pt+Pd from 297.15m in drill hole LIL12-10) and 025-intrusion (1.5m at 1.15g/t from 46.5m) indicating these components of the Thunder Bay North Intrusive Complex are fertile and prospective to host additional concentrations of mineralization. These intrusions have had minimal exploration work completed to date and have low exploration maturity relative to the Current and Escape intrusions.
Current Deposit
Discovery and exploration of the Current Deposit kicked off from 2005 onward when prospectors having discovered PGE mineralized boulders along the shoreline optioned the property to Magma Metals Ltd. Magma optioned the 26 claim Current Lake Property in 2005 and the Beaver Lake claim in 2006 and carried out initial drill programs to test the beneath the mineralized boulders and intersected 11 m of mineralized peridotite grading 2.47 g/t Pt+Pd from 71.5m in the first drill hole (TBND0001). Magma Metals continued exploration on the project till 2012 when it was taken over by Panoramic Resources Limited in June of that year. Between December 2006 and December 2012, Magma/Panoramic drilled 801 core drill holes (185,516m) on the property prior to the property amalgamation by Benton Resources in 2019 and subsequent option to Clean Air Metals.
A first-time historic mineral resource estimate was completed by SRK Consulting Ltd (SRK) in 2009. An updated historic mineral resource was calculated in late 2010 and a Preliminary Economic Evaluation was completed in February 2011 by AMEC Americas (AMEC).
Escape Deposit
In 2006, Kennecott who would be acquired by Rio Tinto in 2014 staked a claim which would become the core of the Escape deposit. Kennecott carried out a number of exploration programs comprising geophysics and drilling between 2010 and 2012. These programs yielded impressive drill intercepts highlighted by drill holes 12CL0009 and 11CL0005. High-grade intercepts from these programs included 33.4m at 7.28gpt Pt+Pd+Au and 2.26% Cu+Ni.
Between 2014 and 2016 Rio Tinto completed outcrop and boulder prospecting throughout the Thunder Bay North Property and reprocessed all Magma Metals/Panoramic geophysical data under an Earn-In JV agreement initiated in 2014. During 2015 and 2016 Rio Tinto drilled 24 core holes (~9500m) into the Project area with 7 holes (2418m) drilled into the TBN Property and 17 holes (7081m) into the Escape Property.
The Rio Tinto option was not fully executed and the Current portion of the project reverted back to Panoramic Resources who carried out limited geological mapping in the project area prior to amalgamation and optioning by Clean Air Metals in 2020.
