Mayfair Gold vs. Tiernan Gold: Which Development-Stage Gold Stock Has More Upside?

We told AI to analyze two gold development companies: Mayfair Gold (TSX-V: MFG)(NYSE: MINE) and Tiernan Gold (TSX-V: TNGD)(OTC: RLTWF). 

We instructed the AI to act as a mining equity analyst, economic geologist, and mining engineer with expertise in Chile and Canada, and evaluate the company based on: 

  • Valuation: market cap, EV, cash/debt, EV/resource, EV/NAV, implied project value.
  • Share structure: basic/FD shares, warrants/options, overhang, financing risk, insider/institutional ownership.
  • Project quality: jurisdiction, geology, resource size/grade, metallurgy, strip ratio/mining method, infrastructure, permitting.
  • Economics: NPV, IRR, capex, opex/AISC, payback, sensitivity to commodity prices, dilution-to-build risk.
  • Commodity exposure: copper/gold/silver/lithium/etc., macro setup, price sensitivity, strategic relevance.
  • Management/board: track record, technical depth, capital markets ability, mine-building credibility.
  • Development path: permits, land/community, funding options, construction complexity, timeline.
  • Upside scenarios: base case, rerate case, takeover case, commodity bull case, exploration/resource-growth case.
  • Risks: technical, financial, political, permitting, dilution, execution, and market-cycle risk.

We gave it the companies' presentations, stock charts, most recent financials and MD&As, and the technical reports for each project. Then asked it to decide which one it would buy as a quality junior mining development speculation, and why, including upside scenarios. Here is what it came up with...

Using June 11 chart prices — MFG C$3.68 and TNGD C$7.40 — my answer is:

I would buy Tiernan over Mayfair for a speculative development-stage gold allocation.
But I’d say that with an important qualifier: Mayfair is the safer, cleaner, more financeable development story. Tiernan is the better asymmetric speculation.

Head-to-head

Metric Mayfair Gold Tiernan Gold Edge
Project Fenn-Gib, Ontario/Timmins district Volcan, Atacama/Maricunga belt, Chile Depends on mandate
Stage PFS with 1.04 Moz probable reserve PEA advancing to PFS; no reserves yet Mayfair
Basic market cap ~C$247M ~C$356M Mayfair cheaper absolute
Estimated EV ~C$215–218M ~C$303M Mayfair cheaper absolute
Share count 67.14M shares; 2.21M options; 0.365M warrants 48.05M shares; 54.83M FD; 5.6M C$6.50 warrants Tiernan cleaner basic count; more warrant overhang
Cash C$32.3M at Mar. 31 ~C$53M per company snapshot / US$36.3M at Mar. 31 Tiernan
Resource / reserve 4.3 Moz indicated; 1.04 Moz probable reserve 9.8 Moz M&I + 1.25 Moz inferred Tiernan on scale
Production profile 64 koz/year LOM; 71 koz/year first six years 330 koz/year first 10 years Tiernan
Initial capex C$450M US$1.019B, roughly C$1.4B equivalent Mayfair
AISC US$1,292/oz LOM; US$1,171/oz first six years US$1,094/oz PEA Tiernan, but lower confidence
Economics C$652M after-tax NPV5, 24% IRR at US$3,100 gold; spot case C$1.37B NPV5, 38% IRR US$1.51B after-tax NPV5, 28.7% IRR at US$2,400 gold; US$2.36B NPV5 at US$3,000 gold Tiernan on NAV leverage
EV/NAV ~0.33x base PFS NAV; ~0.16x spot NAV ~0.15x base PEA NAV after FX conversion Tiernan, risk-adjusted debate
EV/oz ~C$50/oz indicated; ~C$206/oz reserve ~C$31/oz M&I Tiernan
Insider/control ~34% insider ownership; ~$17M insider equity purchases since Oct. 2024 Hochschild/HM Holdings control position, 69.8% noted in filings; presentation shows 69% undiluted / 62% FD Tie, different type of alignment

 

Mayfair’s PFS reserve is 25.13 Mt at 1.29 g/t for 1.04 Moz, all probable, with a 6.0:1 strip ratio over the mine plan. That is much more advanced than Tiernan’s PEA-stage resource case. Tiernan’s Volcan resource is materially larger: 463.3 Mt at 0.658 g/t for 9.804 Moz M&I, plus 1.246 Moz inferred.

Mayfair: better project execution story

Mayfair is trying to thread a needle: build a smaller, higher-grade starter operation under the <5,000 tpd threshold, pursue a shorter provincial permitting path, keep initial capex at C$450M, and get into cash flow faster. That strategy makes sense. The company explicitly contrasts this with the “big but slow” >5,000 tpd path that could trigger a much longer federal process.

The Fenn-Gib PFS numbers are solid at current gold prices: 4,800 tpd, 88.3% recovery, 1.29 g/t LOM grade, 1.47 g/t in the first six years, C$652M after-tax NPV5, 24% IRR, and 2.7-year payback at US$3,100 gold. At the company’s spot case, the NPV rises to C$1.373B, IRR to 38%, and payback falls to 1.7 years.

The problem is that Mayfair’s current PFS mine is small. Sixty-four thousand ounces a year is good, but it is not a major producer’s dream asset by itself. The value proposition is: build the starter mine, generate cash flow, prove the operating thesis, then unlock the remaining resource and district potential. That can work, but the market may not give it full credit until financing is arranged and construction is clearly viable.

The other issue: the project is still gold-price sensitive. At lower gold prices, Mayfair’s economics compress quickly. It is attractive in today’s gold tape, but it is not bulletproof.

Tiernan: bigger, cheaper, riskier

Tiernan is the more interesting speculation because Volcan is simply much larger. The PEA contemplates 293 Mt mined, 1.5:1 strip ratio, 22 Mtpa / 60,000 tpd heap leach processing, 0.63 g/t Au heap feed grade, 64.2% recovery, 3.82 Moz produced, US$1.019B initial capex, US$1,094/oz AISC, and 330,000 oz/year for the first 10 years.

At US$2,400 gold, Volcan’s PEA shows US$1.513B after-tax NPV5 and 28.7% IRR. At US$3,000 gold, that rises to US$2.357B NPV5 and 38.2% IRR. That is why Tiernan screens cheaper: its EV is only around 0.15x base-case PEA NAV after converting the PEA NAV to Canadian dollars.

But the risks are real. The Volcan report is a PEA, and the technical report explicitly cautions that it is preliminary and includes inferred resources that are too speculative to be treated as reserves. Metallurgy also needs more work. The report says recovery improves with higher grade and finer crush size, but cyanide-soluble copper affects cyanide consumption, SART is part of the flowsheet work, HPGR produces fines that require agglomeration, and more testwork is needed for PFS-level confidence.

Jurisdictionally, Chile is mining-friendly in a broad sense, but Volcan is not a casual build. It is high-altitude Atacama/Maricunga, large-scale heap leach, big capex, water/permitting/social/license work, and likely needs a strategic partner or project-level financing. Tiernan does have meaningful advantages: it controls water rights through two developed wells near the project, and the corporate structure is anchored by Hochschild/HM Holdings, which gives it credibility and optionality.

Management and alignment

Mayfair has the cleaner public-market alignment story: ~34% insider ownership, ~$17M of insider equity purchases since October 2024, and a management team pitching a practical Ontario development path. That matters.

Tiernan has a different type of alignment. Hochschild/HM Holdings controls the company, with 69.8% noted in filings and the presentation showing 69% undiluted ownership, 62% fully diluted. That can be good because it gives the asset a technically capable sponsor. It can also be a governance discount because minority holders are along for the ride.

My investment call

I’d buy Tiernan.

Not because it is safer. It is not. Mayfair is safer. Mayfair is more advanced, has a reserve, has a smaller capex hurdle, and has a clearer path to an actual mine.

But Tiernan has the better risk/reward asymmetry:

  1. The market is paying less for more gold. Tiernan trades at roughly C$31/oz M&I, versus Mayfair at roughly C$50/oz indicated and much higher on a reserve-ounce basis.

  2. Volcan is a real company-maker scale asset. A 330,000 oz/year mine for 10 years gets attention from majors, streamers, lenders, and strategic partners. Mayfair’s 64,000 oz/year starter mine is more financeable, but less obviously transformative.

  3. The PFS is the major swing factor. If Tiernan can confirm recovery, capex, opex, and permitting path without major damage to the PEA, the stock can rerate hard. The current valuation already discounts a lot of skepticism.

  4. Gold leverage is much greater. At US$3,000 gold, Volcan’s PEA NPV moves to US$2.357B, and at US$3,600 it moves to US$3.246B. That is the kind of torque I want in a development-stage gold name if I’m accepting permitting and financing risk.

Upside scenarios

For Mayfair, the reasonable upside case is a move from ~0.33x base NAV toward 0.5x–0.7x as it gets permitting/financing clarity. That implies something like C$5–C$7/share. If the market starts valuing it off the spot-gold NPV, a C$8–C$12/share outcome is possible, but that likely needs a credible financing package and confidence that construction will not crush shareholders.

For Tiernan, the first upside case is a successful PFS that validates the PEA. A move to only 0.25x–0.35x of base-case NAV could put the stock roughly in the C$10–C$14 range. If gold stays strong and the market starts valuing Volcan off the US$3,000/oz case, then C$18–C$24 is not crazy. That requires PFS validation, metallurgical confidence, and a credible financing/strategic path.

Bottom line

For a conservative account: Mayfair.
For a speculative development-stage gold bet: Tiernan.

I would own Tiernan before Mayfair at these prices because the discount is large enough to compensate for the higher risk. But I would monitor three things closely: PFS capex, heap-leach recovery/SART/cyanide assumptions, and EIA/permitting timeline. If any of those break the wrong way, Mayfair becomes the better risk-adjusted name immediately.