Resolution Copper by Rio Tinto: status and timeline

Resolution Copper

Mine a deposit that could meet up to a quarter of US copper demand for decades, as grids, EVs and data centres need far more copper than US mines now produce.

ProtoStage 2 of 5

Owns the Oak Flat land since March 2026; exploratory drilling; tribes and 11 judges seek Supreme Court review.

Updated 9d agoChecked 11 Oct0 updates this week

Milestones

Next · Further appeals to the Supreme Court

Congress approves Oak Flat land exchange in defence billDec 2014Complete.
Federal government withdraws environmental reviewMar 2021Complete.
9th Circuit rules 6-5 against Apache Stronghold1 Mar 2024Complete.
Supreme Court declines Apache Stronghold appeal27 May 2025Complete.
Land exchange completed; Forest Service final decision16 Mar 2026Complete.
Further appeals to the Supreme CourtTarget 2026Current milestone.

Most important updates

Upcoming

2026Further appeals to the Supreme Court (next)

Current obstacles

Sacred site and continuing lawsuitsOak Flat is sacred to Apache tribes; challengers and 11 9th Circuit judges are asking the Supreme Court to step in, and a repeal bill exists.
No construction decision or dateWith the land secured, the project still needs final engineering and an investment decision; no first-production date has been given.

Physics limits

Deep ore is costly to reachAt 1.5-2 km down, rock pressure and groundwater make access shafts, ventilation and ground support a large part of the cost of every tonne.
Caving changes the surfaceBlock or panel caving removes support beneath the surface, so the ground above eventually subsides into a large depression; that is central to the Oak Flat dispute.

How it works

3 parts

Deposit

Deep porphyry copper

A large low-to-medium-grade copper body (about 1.5% copper) sits beneath the old Magma mine, far deeper than most copper mines.

Mining

Underground caving

Instead of digging every tonne, miners undercut the ore so it breaks and falls under its own weight into collection points.

Land

Oak Flat exchange

The mine needed 2,422 acres of federal land at Oak Flat, swapped for about 5,300 acres elsewhere; the land passed to Resolution in March 2026.

Spec sheet

Spec	Resolution Copper
Resource (inferred)	1.624 Bt at 1.47% copper^R (reported)
Deposit depth	5,000-7,000 ft (1.5-2.1 km)^R (reported)
Share of US copper demand	Up to 25%^R (reported)
Copper over mine life	Up to 40 billion lb^R (reported)
Mine life	Up to 40 years^R (reported)
Ownership	Rio Tinto 55% / BHP 45%^R (reported)
Spent by early 2023	>US$2 billion^R (reported)

^R reported by the company

Update log

3 updates

About Rio Tinto

The team behind Resolution Copper

Rio Tinto

Lithium, mining, Rincon, battery materials, Argentina

British-Australian mining company developing its first commercial lithium operation at Rincon, Argentina, with $2.5B capital investment.

Secured $1.175B financing in March 2026 from IFC, IDB Invest, EFA, and JBIC for Rincon lithium.
Rincon is Rio Tinto's first commercial lithium operation, targeting 60,000 tonnes per year by 2028.
Shipped first 200 tonnes from Rincon starter plant in March 2026 to Shanghai.

riotinto.com (opens riotinto.com)Company profile →

Founded: 1873153 yrs
Headquarters: United KingdomAustralia
Status: Public
Valuation: public
Works in: MaterialsLithium
Coverage: 2 programs · 5 updateslatest 9d agochecked 11 Oct

Spec

Resolution Copper

Resource (inferred)

1.624 Bt at 1.47% copper^R (reported)

Deposit depth

5,000-7,000 ft (1.5-2.1 km)^R (reported)

Share of US copper demand

Up to 25%^R (reported)

Copper over mine life

Up to 40 billion lb^R (reported)

Mine life

Up to 40 years^R (reported)

Ownership

Rio Tinto 55% / BHP 45%^R (reported)

Spent by early 2023

>US$2 billion^R (reported)

Resolution Copper

Milestones

Most important updates

Upcoming

Current obstacles

Physics limits

How it works

Deep porphyry copper

Underground caving

Oak Flat exchange

Spec sheet

Update log

Fri 2 Oct

Thu 19 Mar

Tue 27 May 2025

About Rio Tinto

Current obstacles

Physics limits

How it works

Deep porphyry copper

Underground caving

Oak Flat exchange

Spec sheet

Update log

Fri 2 Oct

Thu 19 Mar

Tue 27 May 2025

About Rio Tinto