Inside Serra Verde: Latin America's First Ionic-Clay Rare Earth Mine

Pela Ema, in Goiás, is the first commercial ionic-adsorption-clay

rare-earth mine in the Western Hemisphere. Operated by Serra Verde, it

entered commercial production in early 2024, and its ramp is now

underwriting Brazil's credibility as a long-term supplier of the metals

the energy transition needs most.¹

The Pela Ema Deposit

The Pela Ema deposit sits on the Minaçu-Niquelândia axis in northern

Goiás, in a part of central Brazil where deep tropical weathering over

granitic basement rocks has produced exactly the geological conditions

that favour ionic-adsorption-clay rare-earth enrichment.¹ The deposit

was identified and developed through exploration and drilling programmes

extending over several years before construction began.

What makes Pela Ema unusual in the global rare-earth map is not the

total rare-earth content — which is modest by the standards of

carbonatite-hosted deposits — but the distribution of elements. Ionic

clays in this geological setting carry a meaningful share of the

high-value heavy rare earths, including dysprosium and terbium,

alongside the more common light rare earths. That mix matters because it

aligns with what the permanent-magnet industry for electric vehicles and

wind turbines actually needs.

How Ionic-Clay Mining Works

Ionic-clay processing is mechanically simpler than the extraction

methods used for bastnaesite or monazite. The rare earths are loosely

bound to clay minerals and can be released by leaching with a relatively

mild chemistry. There is no high-temperature cracking step, no

aggressive acid bake, and no sulphuric-acid roaster of the kind that

bastnaesite processing normally requires.

That simplicity has two practical benefits. Capital costs per tonne of

capacity are lower than for a conventional rare-earth project, and the

environmental footprint is smaller — with lower energy intensity, less

chemical consumption, and reduced thorium-uranium handling concerns. The

trade-off is that ionic clays typically have lower total rare-earth

content than carbonatite ores, so economics depend on scale and on

processing efficiency rather than on high grade.

Serra Verde's chosen process flow mirrors, with adjustments, the

approach that has been used for decades at ionic-clay operations in

southern China. The novelty at Pela Ema is less in the metallurgy and

more in the operational context: the first time the approach is being

deployed commercially outside the Chinese regulatory and technical

environment.

The Ramp to 6,500 Tonnes

Serra Verde's stated plan is to reach 6,500 tonnes of rare-earth oxides

per year by the end of 2027, over a 25-year mine life.¹ The 2025 output

— part of the 2,000 tonnes that the USGS attributes to Brazil for the

year — represents an early step toward that target.² At steady-state,

6,500 tonnes per year would make Pela Ema one of the ten largest

rare-earth mines in the world by tonnage, and one of the three or four

largest outside China.

The ramp is governed by both geological and operational factors.

Drilling must continue ahead of production to maintain reserve

confidence, processing throughput must scale, and the specific mix of

rare-earth oxides produced must be optimised for the premium-value

fraction. Reaching 6,500 tonnes is not a simple debottlenecking

exercise.

The company has also had to develop its own workforce for a commodity

that Brazil has never produced at scale. Process metallurgists with

ionic-clay experience are rare outside of China, and Serra Verde has

combined expatriate expertise with training of Brazilian engineers. The

longer the operation runs, the more it compounds a national

human-capital base that will underpin Aclara, Meteoric and any future

Brazilian rare-earth projects — a quiet strategic asset that does not

show up in the production statistics.

The Financing Story

The most visible external validation of Serra Verde came from the U.S.

International Development Finance Corporation, which announced in

November 2025 a financing package of up to US$465 million. The loan is

intended to support upgrades at Pela Ema, cover operational expenses and

refinance existing shareholder debt.¹ It is one of the largest DFC

commitments to a Latin American mining project to date.

The strategic logic for the United States is clear. China's export

controls on rare-earth elements, tightened in April 2025 and expanded in

October 2025, highlighted the vulnerability of Western supply chains to

a single dominant source.³ Any producer at meaningful commercial scale

outside China is strategically valuable, and Serra Verde — which has

been operating under Brazilian federal permits and delivering

concentrate into the international market — fits that description.

The same logic is extending to other Brazilian rare-earth projects.

Aclara Resources secured a US$5 million DFC financing package in

September 2025 for its Carina project, and the broader pattern of U.S.

federal financing for Brazilian critical-minerals projects appears

likely to continue through 2026.

A Template for Other Brazilian Projects

Pela Ema's success has established a template that other Brazilian

rare-earth projects are following. Aclara's Carina project, targeting

commercial production in 2028, is working a similar ionic-clay deposit

in northern Goiás. Meteoric Resources' Caldeira project in Minas Gerais

is at the pre-feasibility study stage and is also clay-hosted. Together,

these three projects represent what may become a multi-project Brazilian

rare-earth cluster by the end of the decade.

The cluster logic matters for infrastructure. A single ionic-clay

project can justify a certain scale of roads, power and processing

facilities; three or four projects in adjacent states can share

infrastructure, reducing the per-project cost of market entry.

State-level governments in Goiás and Minas Gerais have signalled support

for the model.

The cluster also produces a natural policy constituency. Multiple mines

in adjacent municipalities translate into tax revenue, local employment

and supplier contracts that give state governments a direct stake in the

success of the industry. That stake, in turn, tends to smooth the

regulatory and permitting path for subsequent projects — a dynamic that

worked for iron ore in Pará and Minas Gerais two decades ago and that

appears to be repeating for rare earths now.

Outlook

Serra Verde's 2026 trajectory is the single most important variable for

Brazilian rare-earth industry narrative. If the ramp continues on

schedule toward 6,500 tonnes per year by end-2027, and if the DFC

financing enables the processing and concentrate-quality upgrades the

company needs, the country's share of global rare-earth supply will

climb steadily through the remainder of the decade. The first

Western-Hemisphere ionic-clay rare-earth mine has proved the concept at

commercial scale; the next step is proving that the concept can be

replicated, and

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