Namibia Critical Metals Successfully Completes Optimization on Hydrometallurgical Flowsheet for the Lofdal Heavy Rare Earth Deposit

HALIFAX, NS / ACCESSWIRE / May 13, 2024 / Namibia Critical Metals Inc. ("Namibia Critical Metals" or the "Company" or "NCMI") (TSXV:NMI)(OTCQB:NMREF) is pleased to announce key results of the optimization test program in preparation for scale-up hydrometallurgical tests for its "Lofdal 2B-4" heavy rare earth project.

Tests were conducted on a 93 kg concentrate sample produced by a flotation pilot plant at SGS Lakefield, using run-of-mine material from the Lofdal Area 4 starter pit. The pilot plant flotation program confirmed the performance of the Lofdal beneficiation flowsheet in a continuous operation and demonstrated the ability to produce an upgrade mineral concentrate. Previous test on bulk flotation concentrate showed promising results in terms of REE extraction and reduced reagent consumption. The current hydrometallurgical testing aims to replicate the previous result using the concentrate produced from the flotation pilot plant. Preliminary confirmatory tests showed consistent high REE dissolution and established a relation between sulphation temperature, REE extraction and iron co-extraction.

Key results include:

• Low (~ 300°C) temperature sulphation yields higher REE dissolution, but also higher iron dissolution. High iron dissolution leads to high reagent consumption to remove the iron in the leach solution.
• High (~ 600°C) temperature sulphation proved to be beneficial in suppressing iron dissolution into the leach solution. The process was able to reduce iron dissolution from around 60% (low temperature bake) to around 30%. This leads to a net reduction in MgCO₃ consumption. However, some REE losses were observed at these high temperature bake conditions.
• Impurity removal process was shown to be successful in removing the iron and thorium and at minimum REE losses whether from high temperature or low temperature sulphation conditions.

Darrin Campbell, President of Namibia Critical Metals, stated:

"I am very pleased to see the hydrometallurgical optimization test work completed with positive results. The unusual primary xenotime mineralization forced us to practically pioneer all beneficiation steps. During our recent visit to the SGS test facilities at Lakefield we were impressed with how our lead consultants at SGS Canada master the optimization of the earlier developed flowsheet. Based on the data, it seems we see further significant reduction of OPEX compared to the previous financial estimations."