Ontario spotlight: Four explorers worth a look – Part 2

Ontario is a global mining powerhouse, rich in copper, gold and lithium among other minerals. Here are four companies to watch. 

Kirkland Lake Discoveries (TSXV: KLDC; US-OTC: KLKLF) has amassed a 400-sq.-km exploration portfolio in the Kirkland Lake region of Ontario’s Abitibi Greenstone Belt, one of the most prolific mining districts in the world.  

Its properties span key fault zones, geophysical anomalies and volcanic-sedimentary contacts within the Blake River Group, a highly prospective assemblage known to host gold and polymetallic volcanogenic massive sulphide (VMS) deposits. 

The company’s current exploration focus is on the KL West project and the Winnie Lake Stock target area. 

Results from its inaugural drill program at KL West last year intersected high-grade copper sulphides from surface and led to two new gold and critical mineral discoveries, confirming a new intrusive-related mineralizing system centered on the Winnie Pluton with a 17-km perimeter. 

Winnie Shaft

Highlights from the Winnie Shaft area included 32.8 metres grading 0.42% copper, 1.11% zinc, 0.13 gram gold, 4.49 grams silver and 331 parts per million (ppm) cobalt starting from 14.2 metres downhole in drillhole KLD25-36. It included 4.7 metres at 1.68% copper, 6.02% zinc, 0.62 gram gold, 10.86 grams silver and 1,120 ppm cobalt.  

Hole KLD-25-34 cut 36.5 metres grading 0.56% copper, 0.96% zinc, 0.11 gram gold, 4.87 grams silver and 365 ppm cobalt starting from 13.5 metres, including 8.3 metres averaging 1.31% copper, 1.95% zinc, 0.23 gram gold, 8.79 grams silver and 527 ppm cobalt. 

Highlights from the Winnie Pluton area include 7 metres grading 0.19 gram gold, 0.81 gram silver, 0.607 ppm tellurium (Te) and 17 ppm bismuth (Bi) starting from 229 metres in drillhole KLD25-31. Hole KLD-25-32 returned 5 metres averaging 1.48 grams gold, 2,14 grams silver, 2.52 ppm Te and 37 ppm Bi from 261 metres depth. 

Other high priority targets are Winnie West, the Wolverine Bend Showing and the Nine Mile area. 

In March, the company acquired the 25-sq.-km Mirado project, about 15 km south of its flagship KL claims. Mirado hosts inferred resources of 10.6 million tonnes grading 1.29 grams gold for 442,000 oz. contained gold. The property hosts the past-producing Mirado mine, and there has been only limited exploration below 150 metres. 

The company kicked off a 25,000-metre drill program in November.  

Kirkland Lake Discoveries has a market cap of about $37 million (US$27 million). 

Onyx Gold

Onyx Gold (TSXV: ONYX) is undertaking a 75,000-metre drill program at its principal Munro-Croesus project, 75 km east of Timmins.  

The 109-sq-km project along Highway 101 hosts the mothballed Croesus mine, which operated between 1915 and 1936 and produced some of the highest-grade gold ever mined in Ontario. 

Munro-Croesus lies about 3 km northwest and along trend of Mayfair Gold’s (TSXV: MFG) multi-million-ounce Fenn-Gib gold deposit and about 1.5 km from McEwen’s (TSX, NYSE: MUX) Black Fox underground gold mine.  

Onyx identified a new northeast-trending structure along the eastern margin of the Argus Main zone in March. Drillhole MC26-267 returned 60 metres grading 0.6 gram gold from 161 metres, including 20.6 metres of 1.1 grams gold.The same hole cut 99.5 metres grading 1.2 grams gold from 344 metres, including 3 metres of 6.4 grams gold and 12.5 metres grading 2.9 grams gold.  

Drillhole MC26-270 cut 28 metres grading 0.3 gram gold from 104 metres, and 32 metres of 0.7 gram gold from 150 metres, including 6 metres of 2.1 grams gold and 1.5 metres of 8 grams gold. 

 

The drillholes show characteristics analogous to the company’s Argus North discovery, made last year about 600 metres to the northwest. It lies about 150 metres north of the regional Pipestone Fault, a major structural corridor that hosts several significant gold deposits in the Timmins camp.  

The discovery hole at Argus North, Mc24-163, returned 69.6 metres grading 3.4 grams gold from 230.4 metres depth, including 34.5 metres grading 5.4 grams gold and 9.5 metres grading 13.9 grams gold. 

Follow-up drilling at Argus North returned 208 metres grading 2.3 grams gold from 78 metres in drillhole MC25-232; 52.2 metres grading 2.2 grams gold from 72 metres in MC25-178; and 91 metres grading 1.8 grams gold from 148 metres in drillhole MC25-168. 

The company has two other projects in Ontari0 — Golden Mile, a 140-sq.-km property 9 km from Discovery Silver’s (TSX: DSV; US-OTC: DSVSF) Hoyle Pond mine; and Timmins South, a 187-sq.-km property adjacent to the Dome mine. 

Onyx Gold has a market cap of about $97 million. 

Rock Tech Lithium  

Rock Tech Lithium (TSXV: RCK; US-OTC: RCKTF) is building Ontario’s first lithium conversion plant in the town of Red Rock, about 100 km east of Thunder Bay. The project is about 60 km from the company’s Georgia Lake lithium deposit.  

The facility will have a production capacity of up to 32,000 tonnes of lithium carbonate equivalent (LCE) a year, enough to supply up to 900,000 electric vehicles. Raw material for the converter will be sourced from Rock Tech’s Georgia Lake spodumene project in the Thunder Bay mining district. 

In April, the company announced a strategic partnership with the BMI Group, a Canadian industrial infrastructure company, to develop the plant. 

BMI will invest $200 million in the project as part of a broader equity structure that will be finalized as the project moves ahead. Rock Tech will retain full control and responsibility for project development, engineering and operations and all key technical, commercial and strategic decision making. 

The deal follows a partnership agreement with Siemens Canada announced at PDAC 2026, under which Siemens will provide state-of-the-art industrial automation technology and a full digital twin for the Red Rock converter. The digital twin — a real-time virtual replica of the plant — will enable performance optimization, predictive maintenance and commissioning. 

 

The converter will be built on BMI’s industrial site in Red Rock, which has access to about 120 MW of power capacity, natural gas, roads and CPKC Rail’s transcontinental mainline. 

The converter will be designed based on Rock Tech’s Guben lithium converter project in Germany. So far, Rock Tech has invested $65 million in the European project, which has been designated as a strategic project under the EU Critical Raw Materials Act. 

The fully permitted refinery will be one of Europe’s first commercial lithium facilities and will produce about 24,000 tonnes of battery grade lithium hydroxide a year, enough to supply roughly 500,000 EVs a year. 

Last October, Rock Tech signed a non-binding memorandum of understanding with Sichuan Calciner Technology of China for potential collaboration on engineering and process optimization. 

Rock Tech Lithium has a market cap of about $112 million. 

Stllr Gold

Stllr Gold (TSXV: STLR; US-OTC: STLRF) is drilling 8,000 metres in is year’s first half at itsmain Tower project in Timmins. 

The first assay results from the project’s Jonpol deposit were released in April. Drillhole MGA26-48 returned 5.85 metres grading 16.52 grams gold from 160.2 metres downhole, and drillhole MGA26-251 cut 22.65 metres of 1.46 grams gold from 49.7 metres depth, including 3.15 metres grading 5.27 grams gold. 

A PEA of Tower last year envisioned an open pit and underground operation producing 273,000 oz. gold annually over 19 years for a total of 5.2 million ounces. The study estimated all-in sustaining costs of US$1,537 per ounce. 

At a base case gold price of US$2,500 per oz., the project delivers a post-tax NPV (at a 5% discount rate) of US$1.01 billion and post-tax IRR of 13%. Initial capital was pegged at $1.9 billion. 

Tower contains 140.4 million indicated tonnes grading 0.89 gram gold for 4 million oz. gold and another 200.3 million inferred tonnes averaging 1.08 grams gold for 7 million oz. gold. 

In March, the company signed an exploration agreement on its Ontario properties with three Wabun Tribal Council member First Nations —Matachewan First Nation, Mattagami First Nation and Flying Post First Nation.  

 

The company is also advancing its Hollinger tailings project, which contains an estimated 50-60 million tonnes of mine tailings from the past-producing Hollinger mine nearby. 

In February, Hollinger became the first project to receive a permit under Ontario’s new provincial Recovery of Minerals regime. The program, enacted last July, aims to streamline and accelerate the permitting process for responsible mineral recovery and environmental remediation outcomes of historical mine sites, including from tailings.  

The project contains 36.2 million indicated tonnes grading 0.35 gram gold for 412,000 oz. of contained gold. Inferred resources add 7.7 million tonnes averaging 0.37 gram gold for 93,000 ounces. 

Metallurgical test results demonstrate 61% recovery via cyanidation. The project has the potential to be a near-term cash-flow opportunity at current gold prices. The Hollinger mine produced 19 million oz. gold between 1910 and 1968.  

Agnico Eagle Mines (TSX, NYSE: AEM) owns an 11% stake in the company. 

Stllr Gold has a market cap of about $247 million.