The Colossus IAC REE Project is located in the State of Minas Gerais, Brazil and comprises of a total of 228.62km² licenses within and around the prolific Poços De Caldas Alkaline Complex which is home to some of the highest-grade IAC intercepts recorded globally.

In August of 2023, Viridis acquired 100% Rare Earth Element (‘REE’) rights to the Colossus IAC (‘Ionic Adsorption Clay’) Project. Since then, Viridis has pursued an aggressive exploration program which has positioned Colossus to potentially become amongst the highest grade IAC projects in the globe.


Ionic Adsorbed Clay (IAC) Rare Earth projects, despite their lower grades are favoured due to simple and cheap processing in comparison to hard rock peers. Due to chemical weathering already liberating Rare Earths from their host mineral (Bastnasite in Poços De Caldas) into ion form, IAC’s require a straightforward ammonia sulphate wash to generate a high-value Mixed Rare Earth Carbonate which can be sent straight to refiners.
Furthermore, IAC mineralisation occurs at surface and requires no drilling and blasting. Once clays are washed and rare earths are precipitated, the ground can be recompacted and restored with simple environmental rehabilitation. This results in significantly lower CAPEX, OPEX and technical risk than majority of REE projects around the globe.
Within Poços De Caldas Alkaline Complex, there is a remarkable combination of the right host rocks, consistent REE mineralisation, tropical environment and origination within a Caldeira which forces deep weathering and formation of aluminosilicates which have ionically bonded with Rare Earths and resulted in the outstanding grades and thickness’s seen to date.

Ionic Clays: A Disruptive Rare Earth Opportunity

Colossus Ionic Clays Chart

Project Highlights & Concessions

The Phase I & II Drill programs at Colossus has resulted in world-class intercepts of IAC REE mineralisation, with significant weighting towards magnet rare earths. Moreover, Viridis has intercepted Rare Earths within all concessions drilled to date, which exemplifies the enormous exploration potential remaining across the Colossus Project and is a testament to the homogenous nature of mineralisation across the Alkaline Complex.

Colossus Project Highlights & Concessions

Northern Concessions

The progress at the Northern Concessions has been tremendous, which originally began as a greenfield exploration opportunity has now identified world-class intercepts of IAC REE’s. The Northern Concessions consist of four licenses (~10km2) which includes two mining licenses that can be fast-tracked towards production.

The mining licenses within the Northern Concessions have a rich history of production which have been subject to continuous clay and bauxite operations for ~70years, furthermore is located proximal to Alcoa’s Alumina Plant which allows Colossus to leverage the existing infrastructure, road access and labour forces exclusively present within the Northern portion of the Complex.

The Northern Concessions have been subject to comprehensive Auger (AG), Diamond (DD) and Reverse-Circulation (RC) drilling, of which highlights include:

  • FZ-RC-29: 5.5m at 14,896ppm [47% MREO] within 18.5m at 6,253ppm TREO

  • FZ-RC-08: 18.0m at 4,268ppm [36% MREO] within 31.0m at 3,080ppm TREO

  • FZ-DDH-06: 33.5m at 3,091ppm [28% MREO] within 48.5m at 2,662ppm TREO

  • CDP-DDH-03: 12.0m at 6,039ppm [32% MREO] within 24.0m at 4,058ppm TREO

  • CDP-DDH-05: 13.0m at 3,664ppm [30% MREO] within 36.0m at 2,604ppm TREO

  • CDP-AG-01: 5.0m at 5,313ppm, ending in mineralization of 6,646ppm TREO

  • FZ-AG-044: 8.0m at 5,441ppm, ending in mineralization of 8,291ppm TREO

  • CJ-AG-019: 11.0m at 5,081ppm, ending in mineralization of 7,790ppm TREO

Colossus Northern Concessions Map
Colossus Northern Concessions Cross Section

Cupim South

The Cupim South prospect is the southern extension and shares analogous weathering profile, saprolite hills and geology of the Cupim Vermelho Norte deposit (104Mt @2,485ppm TREO)1.
The Cupim South prospect was a greenfield exploration opportunity within the Colossus project, which has now identified significant thickness’s of homogenous rare earth mineralisation:

  • CS-DDH-001: 14.0m at 6,177ppm TREO within 24.0m at 4,573ppm TREO from 0m
  • CS-DDH-003: 46.0m at 3,285ppm TREO within 65.0m at 2,799ppm TREO from 0m
  • CS-DDH-005: 27.0m at 2,903ppm TREO within 62.5m at 2,218ppm TREO from 0m
  • CS-AG-036: 4.5m at 6,067ppm TREO ending in 6,034ppm TREO
Colossus Cupim South Cross Section

Capão da Onça

Follow up assays have been received from Capão da Onça since its significant discovery in January 2024 from auger drilling. This discovery represented a regional breakthrough, as no exploration has been conducted for rare earths within the western edge of the complex. The Colossus Project therefore has first mover advantage within this portion of the complex with a dominant land position and on-going exploration endeavours.

These assays in combination with previously announced holes have re-affirmed the understanding that the main portion of the prospect hosts a significantly high-grade corridor, which is underlain by a Tinguaite Breccia – a host rock which is unique to the western edge of the complex. This corridor has repeatedly provided results above ~3,500ppm TREO:

  • CDO-AG-059: 6m at 5,248ppm TREO, ending in 3,646ppm
  • CDO-AG-045: 4m at 6,870ppm TREO, ending in 3,918ppm
  • CDO-AG-071: 7m at 8,277ppm TREO, ending in 8,275ppm
Colossus Capao da Onca Map


Maiden diamond and auger assays were reported in January which signify another breakthrough discovery within the Colossus Project. This was previously a greenfield concession with no adjacent exploration or sampling completed. Maiden drilling has revealed a homogenously mineralised saprolite profile approximately 10-20m thick with consistent grades of ~3,000ppm TREO:

  • RA-AG-020: 10.0m at 3,033ppm TREO, ending in 3,630ppm
  • RA-AG-030: 8.0m at 3,083ppm TREO, ending in 4,868ppm
  • RA-AG-026: 11.0m at 2,885ppm TREO, ending in 6,066ppm
  • RA-DDH-003: 15.5m at 3,223ppm TREO within 24.0m at 2,678ppm TREO from 0.5m.
  • RA-DDH-001: 10.5m at 3,016ppm TREO within 21.0m at 2,418ppm TREO from 8m.