Copper producers have just closed one of the strangest reporting seasons in the industry's recent history: several of them pulled the metal out of the ground last quarter at essentially no net cost. Hudbay Minerals, which mines copper concentrate in Manitoba, Saskatchewan and Peru, reported a consolidated cash cost of minus $0.40 a pound — the gold it sells alongside the copper covered the entire bill, contributing 38% of gross revenue. Southern Copper, the biggest producer of the group, put its cost after by-product credits at $0.05/lb against a realized copper price of $6.04/lb, up 40% on the year.

Those results sit under a nine-company group of copper, aluminum and rare-earth miners that supply the wire, busbar and magnets consumed by data-center construction. J.P. Morgan estimates a single large AI facility can require up to 50,000 tonnes of copper, and BHP projects data-center demand growing from about 500,000 tonnes a year now to some three million by 2050. The group has gained about 19% over the past month. The businesses beneath it did not move in anything like that pattern.

The month was really four sessions

The gains are wildly uneven: Ero Copper +33.3%, Hudbay +21.4%, USA Rare Earth +15.5%, Teck +9.6% and Freeport-McMoRan +9.1%, against Alcoa +2.9%, Rio Tinto +2.2%, Southern Copper +1.7% and BHP +1.5%. Remove each company's two best trading days from the window and six of the nine turn negative — Southern Copper at -10.2%, Alcoa at -7.2%, BHP at -6.5%. Only Ero (+12.9%) and Hudbay (+3.9%) survive the exercise.

Those best days were shared. On 4 August every member rose at once, with Southern Copper up 4.98% and Freeport up 5.75% while a copper futures fund gained 1.26% — the equities amplified a modest commodity move. Similar synchronized gaps landed on 21 July, 30 July and 7 August. The mechanism is visible in the metal itself: September copper futures in New York hit a record $6.7140/lb on 12 August, London cash copper closed at a $207.50-a-tonne premium to the three-month contract as immediately deliverable metal grew scarce, and Washington exempted refined copper from Section 232 tariffs on 31 July before the Commerce Department recommended a phased 15% levy from January 2027. A smelter outage on ore from Freeport's Grasberg mine tightened supply further.

Step back and the advance shrinks. Over three months the nine average -5.8%. Over six months they average +2.4%. The +80% twelve-month figure was earned almost entirely before February.

What the numbers say, name by name

Southern Copper, a $154bn integrated miner and smelter controlled by Grupo Mexico, posted the group's best quarter: revenue $4.29bn, net income $1.67bn, up 71.5%. Yet its copper output fell 3.5% to 230,662 tonnes, with Peru down 12% on lower ore grades at Toquepala and Cuajone. Full-year guidance still went up 1%, to 917,000 tonnes, and management expects 2027 to look much the same. It is also the group's most expensive share: 27.0x trailing and 24.1x forward earnings, 15.8x EV/EBITDA and 12.1x book value. Flat production at a rich multiple is why the best quarter drew the smallest response.

Ero Copper, a $3.5bn Brazilian producer running the Caraiba complex in Bahia and the Tucuma mine in Para, is the one name whose share move the accounts support. Revenue grew 73.9% to $284.3m, gross margin reached 42.7%, cash costs ran at $2.42/lb, and renegotiated smelter treatment charges will save roughly $20m in the second half. Net debt fell $38m to $453m, taking leverage to 0.8 times from a 2.6 times peak. Despite a 33% month, its price against gross profit is unchanged from early May, and forward earnings (8.7x) sit below trailing (11.3x). The caveat is consensus itself: after 60% revenue growth this year, analysts model 9.5% next year and declines after that.

Hudbay, at $11.9bn, grew revenue 21.4% to $651m with gross profit up 51.2% and guided 2027 copper output 24% higher, to about 150,000 tonnes. But its forward price/earnings of 17.7x now sits above its trailing 15.8x, and its price-to-gross-profit has expanded from 7.5x in May to 12.2x. The business is improving; the shares repriced faster.

Freeport-McMoRan, the largest listed copper miner, was the only one whose revenue fell — down 7.3% to $7.03bn as Grasberg recovered from disruption. Output there doubled to 69,000 tons a day by June from 34,000 in April, and the company cut full-year unit net cash cost to about $1.90/lb while guiding second-half copper sales more than 20% above the first. Management framed the leverage plainly: every $0.10/lb on the copper price is worth about $390m of annual EBITDA. At 32.8x trailing and 22.8x forward earnings, with its multiple of gross profit up from 8.3x to 13.8x since May, much of that is already priced.

Alcoa, the $13.2bn bauxite, alumina and aluminum producer, is the group's contradiction. Record revenue of $3.97bn, up 31.4%, and a record $1.1bn of aluminum-segment EBITDA came alongside a cut to full-year alumina output — 9.5-9.6 million tonnes, from 9.7-9.9 million — after an oxalate outbreak at the Pinjarra refinery and cyclone-related gas disruption, plus an earnings miss. It also agreed to buy South32's bauxite and aluminum assets for $4.1bn, and fell about 13% on leverage and execution worries. It is down 24.3% over three months and trades at 7.6x forward earnings — the cheapest and the weakest at once.

Rio Tinto and BHP, the two diversified majors, contributed almost nothing to the month despite carrying the highest analyst conviction in May. Teck Resources, the Canadian copper and zinc miner, rose 9.6% but is down over three months, with disruption concerns at its Quebrada Blanca operation part of the supply story lifting the metal.

USA Rare Earth, a 132-employee magnet developer building a US mine-to-magnet chain, booked $5.8m of revenue at a negative 69.8% gross margin and a $46.3m operating loss. It holds $1.5bn of cash, expects first magnet sales by end-2026 at a 600-tonne run rate, and agreed to buy Brazil's Serra Verde for about $2.8bn. At 201x trailing sales, the valuation rests on capacity that does not exist yet.

The setup

Where it stands — A 19% month in data-center metals came from four shared macro sessions; the group is down about 6% over three months. Would confirm — Freeport's third-quarter copper sales landing more than 20% above the first half, as guided. Would invalidate — New York copper falling back below $5.50/lb, removing the realized-price support under third-quarter results. Watch next — USA Rare Earth's Serra Verde close, due by end-August; third-quarter miner results from late October. Valuation — Ero at 11.3x trailing and 8.7x forward earnings against Southern Copper's 27.0x and 24.1x.