American Rare Earths Ltd (ASX:ARR)’s magnetic separation has increased the total rare earth elements (TREE) grade from the La Paz Project in Arizona by 216% through concentration testing of surface samples with the scandium grade also increasing.
The tests resulted in TREE concentrate increasing from 552ppm to 1744ppm (+216%) recovering 74.7% of available TREE while scandium concentration increased from 16ppm to 30.4ppm (+90%) recovering 43.8% of available scandium.
This preliminary test-work demonstrates that ore from La Paz can be effectively concentrated using magnetic separation, selective grinding and direct RE flotation and this also resulted in a 76% reduction in the ore mass for surface samples
"An important step"
ARR managing director Keith Middleton said: “ARR is extremely pleased with the preliminary test results at La Paz.
“These results demonstrate that ore material from La Paz can be effectively concentrated using proven technologies.
"Reducing ore material by 76% while recovering nearly 75% of TREE, with a 216% increase in TREE grade, is an important step in the technical evaluation of La Paz, where we plan to deliver, low-cost rare earth elements, for the US domestic and military supply chain.”
Background
Saskatchewan Research Council (SRC) performed a series of magnetic separation tests and liquid flotation tests on surface rock samples collected in the La Paz resource area.
The objective of the test-work was to determine if REE elements can be concentrated from ore rock using magnetic and/or liquid flotation as a means of pre-processing material used for later refining.
ARR provided approximately 72 kilograms of material from 32 rock samples collected in early 2021 across the La Paz resource area.
Positive outcomes
Reducing mass of feed material (pulverised ore) concentrating the mineralised material (ore), could reduce operational expenses during processing.
Such cost savings would be a function of having less material (processed ore) to be leached.
Less material to be leached could reduce the cost of leaching chemicals and reduce the volume of tailings and the gangue material removed by magnetic separation would be void of any chemical treatment.
This clean, pulverised gangue material would likely be safe to return to the void of an open pit mine during mine reclamation.
ARR believes that a project with less volume of chemically treated tailings and a more simple, cost-effective reclamation process has a better opportunity for permit approvals compared to not having these advantages.
This responsible mining approach is consistent with the company’s Environmental, Social and Governance (ESG) values.
The company has started an advanced metallurgy work program at Nagrom Ltd in Western Australia utilising core selected from the 2021 diamond core drilling program with the goal being to improve on these preliminary results and develop an advanced mineral processing and metallurgy flow sheet.