By Penny Langford
Rio Tinto and Codelco finalized a landmark joint venture (JV) in early 2026. This $900 million agreement focuses on the Salar de Maricunga in Chile. It represents a major strategic shift for Rio Tinto. The company is moving deeper into the battery metals space. This move also marks a turning point for Chile’s National Lithium Strategy.
The partnership combines global capital with state control. Codelco holds a majority stake of 50% plus one share. Rio Tinto owns the remaining 49.99%. This structure follows Chile’s mandate for state participation in "strategic" salt flats. For Rio Tinto, it provides a low-cost entry into one of the highest-grade lithium deposits in the world.
The $900 Million Agreement Structure
The investment is structured in three distinct tranches. This phased approach de-risks the capital deployment for Rio Tinto.
- Initial Tranche: Approximately $350 million was committed at the closing of the deal. These funds support immediate technical studies and pilot programs.
- FID Tranche: An additional $500 million is triggered upon a Final Investment Decision (FID). This milestone depends on successful feasibility studies and environmental permits.
- Production Bonus: A final $50 million is contingent on reaching commercial production. The current target for first production is the end of 2030.
This deal allows Codelco to leverage Rio Tinto’s operational expertise. Codelco is the world’s largest copper producer, but it is a newcomer to the lithium brine sector. Rio Tinto brings experience from its Rincon project in Argentina and its European lithium assets.
Why Maricunga Matters
Salar de Maricunga is Chile’s second-most important lithium asset after the Salar de Atacama. It is located in the Atacama Region at a high altitude. The brine is exceptionally high-grade. However, the geology is complex.
Maricunga has remained largely untapped compared to Atacama. Environmental and social scrutiny in the region is high. The salt flat is smaller and more sensitive to water table changes. This sensitivity is why the JV is prioritizing Direct Lithium Extraction (DLE) technology over traditional evaporation ponds.
The Role of Direct Lithium Extraction (DLE)
Traditional lithium production uses massive evaporation ponds. These ponds take up significant land area. They also lose massive amounts of water to the atmosphere. Chile’s government now favors DLE technology for new projects.
Rio Tinto is deploying Adsorption-based DLE (A-DLE). This method uses specialized sorbents to pull lithium ions directly from the brine. The "spent" brine is then reinjected into the salt flat. This process maintains the hydrostatic balance of the salar.
Key Advantages of A-DLE at Maricunga:
- Higher Recovery: A-DLE can achieve recovery rates of 85-95%, compared to 40-50% for evaporation.
- Speed: The extraction process takes hours or days rather than 18 months.
- Water Conservation: Reinjection reduces the impact on local ecosystems and water rights.
- Small Footprint: The physical plant occupies a fraction of the land required for ponds.
However, commercial-scale DLE remains a challenge. Rio Tinto must prove that its technology can handle the specific chemical profile of Maricunga’s brine at scale. The 2026-2027 period is critical for pilot testing and data collection.
Chile’s National Lithium Strategy: The 2026 Landscape
The Maricunga JV is a flagship project for Chile’s National Lithium Strategy. When President Gabriel Boric launched the strategy in 2023, it faced skepticism from global investors. Critics feared that the "state-majority" requirement would stifle investment.
By 2026, the narrative has shifted. The Kast administration has maintained the core state-majority framework for strategic assets. However, it has streamlined the permitting process. The government merged the Mining and Economy ministries to reduce bureaucracy.
Chile’s Lithium Market Position (2026 Projection):
| Metric | 2024 Actual | 2026 Estimate | 2034 Target |
|---|---|---|---|
| Global Market Share | ~23% | ~21% | ~25%+ |
| Total Production (LCE) | 280,000 t | 315,000 t | 430,000 t |
| Number of Active Salars | 1 (Atacama) | 2 (Atacama, Maricunga) | 5+ |
| Revenue Model | Royalty/Tax | JV Dividends + Royalty | Multi-stream |
The Maricunga deal proves that major miners are willing to accept minority equity for access to world-class resources. This follows a similar deal between Codelco and SQM for the Atacama operations.
Rio Tinto’s Strategic Pivot
Rio Tinto is repositioning itself for the energy transition. Historically, the company relied on iron ore for the bulk of its earnings. In 2026, the company is diversifying.
The Maricunga JV complements Rio’s other lithium interests. The Rincon project in Argentina is moving toward its first phase of production. The Jadar project in Serbia remains a long-term goal despite regulatory hurdles. By entering Chile, Rio Tinto secures a foothold in the "Lithium Triangle" under a stable, albeit state-centric, legal framework.
The company is also leveraging its leadership in autonomous haulage and remote operations. These technologies will likely be integrated into the Maricunga facility to lower operational costs in the high-altitude environment.
Risks and 2026 Outlook
The road to 2030 is not without obstacles. Several risks could delay the Maricunga project:
- Technology Scale-up: DLE has worked in pilots, but full-scale industrial deployment is still new. Any technical failure at Maricunga would be a blow to Rio Tinto’s lithium ambitions.
- Lithium Prices: Prices stabilized in 2025 after a massive crash. However, sustained low prices could impact the FID timeline. Rio Tinto is taking a long-term view, positioning itself as a low-cost producer for the 2030s.
- Community Relations: Indigenous groups in the Atacama region are highly protective of water rights. The JV must secure a social license to operate. This requires transparent communication about brine reinjection.
Despite these risks, the Maricunga breakthrough is a win for both parties. Chile secures a partner with deep pockets and technical skill. Rio Tinto secures a seat at the table in the world’s premier lithium jurisdiction.
As the copper deficit continues to drive Codelco’s focus, the Rio Tinto partnership allows the state miner to expand into lithium without overextending its own management capacity. The next 18 months will determine if Maricunga can meet its 2030 production target.
Featured Lead: M&A Social Snippet
LinkedIn / X Snippet:
? M&A Alert: Rio Tinto and Codelco finalize $900M JV for the Maricunga lithium project! ??
This deal is a cornerstone of Chile’s National Lithium Strategy, combining state control with Rio Tinto’s DLE technology and global capital. With a 2030 production target, the "Lithium Triangle" just got a lot more competitive.
Is the state-majority model the new blueprint for critical minerals? Read our full analysis of the Maricunga breakthrough.
#MiningNews #Lithium #RioTinto #Codelco #EnergyTransition #ChileMining #CriticalMinerals
