RecommendationsDue to the level of detail and effort invested in...

Recommendations
Due to the level of detail and effort invested in this scoping study, a prefeasibility study should be
realised in approximately 12 months based on the collection of additional data to support the permitting
process, hydrology, geotechnical engineering, and geologic mapping including sampling. Mine
engineering and further processing testwork is needed to better understand, design, and cost the
Halleck Creek Project.
Geologic sampling and mapping s needed to determine extents of mineral resource and to identify
additional high-grade areas, and to guide future exploration efforts at the Project. Infill drilling is
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recommended within the Cowboy State Mine area to increase resource classification, and to collect
hydrological and geotechnical information to enhanced design parameters, engineering factors and
associated economics at the prefeasibility level.
Bulk sampling and core drilling is needed to advance metallurgical testwork, specifically comminution
and concentration testing. Comminution testing is recommended to define crushing and grinding
processes featuring High-Pressure Grinding Rolls (HPGR) to identify particle size distribution, energy
consumption and associated costs.
Concentrate testing is recommended to determine equipment required for primary gravity separation to
validate mass balance and concentration efficiency. Gravity separation testing at specific gravities
above and below 2.7 is recommended to remove less-dense gangue material from REEE ore which
represents about 77% of the mineralised material.
Extensive extraction and refining testwork is recommended to define practical methods for leaching,
possible calcining, impurity removal, and solvent extraction to produce specific rare earth oxides. These
tests will determine base-case parameters (temperature, pH, residence time, molarity, etc.) and
reagents (sulfuric acid, sodium hydroxide, etc.) for a future demonstration plant. The solvent extraction
testing will begin with initial batch tests moving toward continuous testing when the quantity of feedstock
allows. Solvent Extraction test parameters include feed acidity, separation coefficients, and settling time
among others. Waste water streams need to be quantified and analysed to aid in the mass balance.
It is recommended that ARR begin developing permitting and baseline environmental needs in
conjunction with regulatory agencies. It is also recommended that ARR develop a framework for
community engagement while reaching out and understanding the community needs.