Posted on 01 Dec 2025
The Brazilian prosecutor’s office (MPF) has sounded the alarm over the viability of two rare earth projects in the state of Minas Gerais, Kallanish learns.
It comes as Brazil is boosting the development of rare earth mining amid soaring demand for ex-China supplies. Currently, the only active mine is Serra Verde’s Pela Ema in the state of Goiás.
In a statement earlier in the week, the MPF has recommended that the State Environmental Foundation (Feam) and the State Council for Environmental Policy (Copam) suspend the analysis of the environmental licensing processes for two deposits. The projects affected are Viridis Mining’s Colossus, which is considered one of the largest ionic adsorption clay projects worldwide and is targeting a final investment decision next, and Meteoric Resources’ Caldeira, which is due to start production in 2028.
Copam was due to vote on licensing on Friday, but the MPF asked to suspend it to “allow for further studies and consultations addressing the outstanding environmental and social risks.”
Both are located on the Poços de Caldas volcanic plateau and are classified as holding the highest level of pollution potential, the government agency says. The two projects are each expected to process 5 million tonnes/year of clay using acid leaching, which the MPF says “requires the adoption of measures to prevent serious damage, given that scientific knowledge about the impacts of rare earth mining is currently limited.”
Another concern is their proximity to the Caldas Decommissioning Unit, a deactivated complex that stores radioactive waste and materials. The MPF has requested a nuclear safety statement from the relevant authorities, plus complementary studies to assess whether chemical leaching can capture other heavy metals, such as thorium and uranium, which could generate radioactive waste.
The MPF notes that the deposits may contaminate aquifers in an area at risk of water scarcity. It adds that Colossus, in particular, is lacking the necessary permits to be within the security area of Poços de Caldas Airport.
As for Caldeira, the MPF says that the company has not carried out free, prior and informed consultations with the Indigenous and Quilombola communities, which “prevents the licence from proceeding.” The project would also include part of an environmental protection area (APA) where municipal law prohibits mining activities.
Viridis and Meteoric were contacted for comment.
Source:Kallanish
