Paulo Macro — Update on my Largest Copper Position: When a Door Closes, a Window Opens
"There is nothing wrong with this asset… I think there is something wrong at Rio." Rio Tinto's Nuton walks away from Aldebaran's Altar earn-in, the stock drops -30%, and Paulo buys the dip — because Rio's exit removes the M&A ceiling and puts ALDE in play for 2026.
One-line take: Paulo's largest copper equity position, Aldebaran Resources (ALDE.CN, C$3.00, ~US$400mn FD), just published its flagship Altar PEA — US$2.0bn NPV8 / 20% IRR at $4.35/lb Cu ($3.3bn / 28% at $5/lb), 48-yr life, $1.6bn capex on a rare ~50-yr, 32-billion-lb district-scale deposit — and days later Rio Tinto's Nuton subsidiary walked away from its staged US$250mn earn-in. The stock fell -30% on historic volume in "a massive overreaction"; Paulo "channeled his inner Shrub" and filled bids in the $2.60s. His read: nothing is wrong with the asset — Rio is the problem (new CEO Simon Trott cost-cutting: Jadar mothballed, Arizona Sonoran pro-rata refused, travel ban; Rio only ~#9 in mined copper and "seems lost"). Crucially, Rio's exit removes the M&A ceiling: ALDE now owns 80% of a district-scale Argentine asset with competitive tension restored (South32 15% holder, Sibanye 14% + 20% of Altar, Glencore next door at El Pachon — the Filo/Jose Maria infrastructure template). At ~0.15-0.25x NAV, "ALDE is in play in 2026 and the market does not realize it" — he's a buyer. Back-filled post (predates the source's other archived notes).
1. Stocks & names mentioned
| Ticker | Name | Research | View | What's said | Source |
|---|
| ALDE | Aldebaran Resources | SA · STK | Positive | His largest copper equity position (ALDE.CN, C$3.00, ~US$400mn FD). The Altar PEA delineated a US$2.0bn NPV8 / 20% IRR at $4.35/lb Cu ($3.3bn / 28% IRR at $5/lb), 48-yr life, $2.02/lb cash cost, $1.6bn capex — a rare ~50-yr, 32-billion-lb, 0.4% Cu district-scale asset (ALDE owns 80%). After Rio's Nuton walked from its staged US$250mn earn-in, the stock fell -30%; Paulo "channeled his inner Shrub" and bought the $2.60s. With Rio's M&A ceiling removed, "ALDE is in play in 2026 and the market does not realize it" — ~0.15-0.25x NAV, a buyer. | read ↗ |
| SBSW | Sibanye Stillwater | QT · SA · STK · FA | Neutral | Original owner of Altar; staged 80% down to Aldebaran over several years via milestones and still holds 20% of the project plus ~14% of ALDE stock. Framed as a likely eventual seller — no investment view expressed. | read ↗ |
| SOUHY | South32 | SA · STK | Neutral | BHP's spun-out metals arm owns 15% of Aldebaran (paid ~C$1.01 for most of its 2023 pro-rata). Cited as one of the strategic bidders — with Glencore, Sibanye, the Chinese and other majors — whose competitive tension is restored now that Rio/Nuton is out of Altar. | read ↗ |
| GLNCY | Glencore | QT · SA | Neutral | Owns the neighboring El Pachon copper project in Argentina — flagged as a natural ALDE acquirer and infrastructure-sharing partner ("Why not team up with Glencore at El Pachon down the road like Filo did with Jose Maria? One road, power line, and water supply is cheaper than two"). | read ↗ |
| ASCU | Arizona Sonoran Copper | SA · STK · FA | Neutral | Another Nuton bio-heap-leach test site (Cactus project) where Rio refused to exercise its pro-rata rights — cited as evidence of Rio's cost-cutting retrenchment (alongside Jadar and the travel ban), not an asset problem. | read ↗ |
| TECK | Teck Resources | QT · SA · STK · FA | Neutral | Passing merger reference: a successful Teck–Anglo tie-up would push Rio further down the mined-copper rankings (Rio already only ~#9), part of why Paulo reads Rio as "lost" on copper growth. | read ↗ |
| RIO | Rio Tinto | QT · SA · STK · FA | Negative | Negative on the operator, not the asset: new CEO Simon Trott (three months in) is cost-cutting — Jadar lithium mothballed (~$700mn sunk), Arizona Sonoran pro-rata refused, an internal travel ban — and "seems lost." At only ~#9 in mined copper and "not investing, so won't grow," Rio let Nuton walk rather than pay $30mn for a PFS on a US$2bn project. He'll buy Rio back "later… and higher" when the big boys inevitably chase growth again. | read ↗ |
ALDE is a CSE/TSXV-listed junior (OTC: ADBRF) and ASCU/SOUHY are non-US listings, so those rows carry SA/STK only. "View" reflects how each name was framed in this note (Positive = a held position Paulo is adding to; Neutral = shareholder/neighbor/comp context; Negative = the operator he's souring on). Private holders Route One (SF private equity, ~44% of ALDE) and Nuton (Rio's bio-heap-leach subsidiary) are discussed but are not investable rows. Written post — no video, so the "Source" links open the Substack note. Research: QT Qualtrim · SA Seeking Alpha · STK Stock Analysis.
2. Talking points
The macro backdrop — a copper M&A wave incoming
- Paulo remains a bull on base metals and uranium. In copper especially he expects "a significant wave of M&A that cleans out the 'middle' among junior producers and select advanced explorers before the mania of flying garbage really gets going" — the thesis he set out in The Three Phases of a Mining Bull.
- His edge-seeking process: torque the upside among junior producers/explorers while limiting the downside (first laid out when he presented this position in October 2024, followed up in "When Macro & Micro Stars Align" in February).
The Altar PEA — a US$2bn+ mine delineated
- Aldebaran's flagship Altar project PEA (at $4.35/lb Cu, $2,500/oz gold): NPV8 US$2.0bn, 20% IRR, 48-year mine life, $2.02/lb cash cost ($2.59 AISC), 4-year payback on $1.6bn capex.
- At spot $5/lb Cu (the current long-term Street price) and $4k gold: NPV8 US$3.3bn, 28% IRR, 2.2-year payback.
- Resource: 32B lbs Cu + 6.8Moz gold (~70% M&I), grading 0.4% Cu — "a large, generational asset of ~50 years… is rare." The PEA "exceeded my own ~$1.5bn valuation expectations."
Ownership structure
- Aldebaran owns 80% of Altar; Sibanye Stillwater (the original owner) holds the other 20%, having staged ALDE in via milestones.
- The ALDE share register: Route One (SF private equity) ~44%, South32 ~15%, Sibanye Stillwater ~14%, management ~5%.
The Nuton earn-in — a masterstroke for ALDE
- In Nov-2024 ALDE signed Nuton (a Rio Tinto subsidiary) to pay $10mn at signing, $20mn on an updated MRE, $30mn after the PEA, and $190mn after a PFS — US$250mn total for 20% of Altar (leaving Sibanye 20%, ALDE 60%).
- Signed when junior capital markets were "largely closed" and copper was $4/lb (vs $5 today), the deal had Nuton fund $30mn of drilling + a PEA that proved a $2bn+ mine. "ALDE management pulled a rabbit out of the hat."
What is Nuton?
- Rio's proprietary copper bio-heap-leach program — microbial "bugs" that accelerate natural sulphide leaching to lift recoveries on "difficult" ores (waste, tailings, complex/arsenic-bearing, water-restricted). It is Rio's answer to Freeport/BHP's Jetti technology; the goal is to make 0.1-0.2% Cu tails economic.
- Nuton has test agreements with several juniors — Arizona Sonoran (Cactus), Excelsior (Gunnison), Regulus (AntaKori) — and is run by Rio's former head of acquisitions ("a 'Google Area 120' incubator: find deposits where the tech works, fold them into Rio").
Nuton walks — and the -30% overreaction
- Over the weekend Nuton declined its next $30mn payment and walked, forfeiting its US$30mn sunk cost. ALDE fell over -30% Monday on historic volume (1.3mn shares Mon, 300k Tue) before stabilizing at $3.00-3.10.
- Paulo "channeled his inner Shrub and gave thanks, filling several bids in the $2.60s." Despite the drop, ALDE sits where it closed Oct-8 and is +60% on the year.
Why did Nuton walk? Because Rio is the problem
- No edge at Altar: the PEA showed a Nuton leach plan was "a wash" vs a conventional mine (slightly more cashflow, slightly lower NPV) — if the tech doesn't move the needle, Nuton moves on.
- Rio seems lost: new CEO Simon Trott (an operations lifer) is cost-cutting to "play with the MBA/PE boys" — Jadar lithium mothballed (~$700mn sunk on a $2.5bn+ project), Arizona Sonoran pro-rata refused, an internal travel ban. Rio is only ~#9 in attributable mined copper (and would fall further if Teck–Anglo merge). "Rio is not investing, so Rio won't grow… they'll be back buying assets — only it will be later… and higher."
Nothing wrong with the asset — and it can fund itself
- "There is nothing wrong with this asset, and everything from the PEA stands." Paulo has been to Altar and trusts CEO John Black's team (he crosschecked with management Monday morning).
- The lost $30mn PEA-to-PFS bridge "must now be rebuilt" — but ALDE has levers that don't require an equity raise: a 0.5% net smelter royalty to a streamer/PE could fund it and "put to bed any questions about the asset." The company has $10mn cash; the ~$20-30mn PFS need "can be raised in 3-6 months, not now."
- Dilution discipline as a quality tell: past raises were all non-brokered private placements at a premium — C$20.5mn in Sep-23 at 88c (South32 paid C$1.01), C$6mn of 70c warrant exercises, a C$14mn South32 entry in Aug-22. "Any junior that delivers a $2bn NPV PEA burning only C$30mn of raised equity in 2 years is… rare."
The hidden win — Rio's exit removes the M&A ceiling
- Paulo's "biggest question since they signed the Nuton deal: how do you maintain competitive tension in the room with Rio there?" A 20% Rio owner would sit "in the driver's seat on any M&A" and deter rival bidders — "why would a competitor launch an offer if Rio could come over the top with a counter?"
- "Well, Rio paid for Aldebaran's PEA, and now Rio is out of the way." ALDE owns 80% of a world-class, district-scale asset in Argentina (political risk "greatly diminished" after Milei's midterm win) "just when copper is potentially re-racking to a new price deck."
ALDE is in play in 2026 — the re-rate math
- Before, Paulo assumed a takeout only after the 2027 PFS. Now: "ALDE is in play in 2026 and the market does not realize it." A buyer who waits for the PFS will see $5/lb copper in the study → Altar NPV goes to $3.3bn and ALDE's NAV from $1.6bn to $2.6bn — so ALDE trades at 0.15x NAV at $5 copper (0.25x at $4.35 today). "Why not buy ALDE and do the Feasibility Study your way?"
- The template: team up with Glencore at neighboring El Pachon "like Filo did with Jose Maria — one road, power line, and water supply is cheaper than two." At <$400mn mkt cap, "I'm personally a buyer rather than a seller."
3. In plain English
A jargon-free summary of the thesis behind each name — what it actually is and why that view. (Plain-language companion to the table above; renders on each ticker's consolidated page.)
ALDE — Aldebaran Resources Positive
Aldebaran is a small Canadian mining company ("junior") developing a huge copper-gold deposit called Altar in Argentina. It just published a PEA — an early engineering study estimating what the mine would be worth if built — and the numbers were strong: about US$2 billion of value (NPV, today's worth of future cash discounted 8%) at conservative copper prices, rising to US$3.3 billion at today's $5/lb copper, over a ~50-year life. Aldebaran owns 80% of it.
A year ago Aldebaran signed a clever deal: Rio Tinto's tech unit "Nuton" agreed to pay up to US$250 million in stages to fund the studies, in exchange for a 20% slice — so Rio effectively paid for Aldebaran's PEA. Then Rio suddenly walked away. The stock crashed -30% because investors feared something was wrong with the deposit. Paulo's argument is the opposite: nothing is wrong with Altar — the problem is Rio, a giant that's slashing costs and "seems lost" under a new CEO. He bought the panic in the $2.60s.
The real payoff is subtle: while Rio was in the deal it acted as a ceiling on any takeover (no rival would bid if Rio could just counter). With Rio gone, Aldebaran is a clean, 80%-owned, world-class asset that other majors (South32, Glencore next door, Sibanye) can now compete for — and the study can be re-run at higher copper prices, mechanically lifting the value. At roughly 15-25 cents on the dollar versus that estimated value, Paulo thinks Aldebaran gets taken over in 2026 "and the market does not realize it." He's a buyer.
RIO — Rio Tinto Negative
Rio Tinto is one of the world's biggest miners, but only about #9 in copper production. Paulo has turned negative — not on any single asset, but on the company's direction. A new CEO who came up through operations is trying to prove himself by cutting costs hard: he mothballed a big European lithium project (after sinking ~$700 million into it), refused to fund his share of another copper test project, and even imposed an internal travel ban. Letting Nuton walk away rather than pay a mere $30 million to see the next study on a $2 billion project is, to Paulo, the same story — a company retrenching instead of investing.
His logic: "Rio is not investing, so Rio won't grow." Miners that stop investing eventually have to chase growth by buying assets again — but they always do it later, at higher prices, once the cycle has run. So Paulo would rather own the cheap junior (Aldebaran) that Rio just vacated, and buy Rio back "later… and higher." A negative on the operator, not a permanent write-off.
Key points extracted from the paid Substack post (in transcript.txt) for personal study. Not investment advice. © Paulo Macro for source material.