Astron Corporation upgrades reserves at critical Donald rare earths and mineral sands project

Astron Corporation (ASX: ATR) has upgraded the size of its reserves at its flagship Donald rare earth and mineral sands project in western Victoria, which is already one of the world’s largest undeveloped critical minerals assets.

The enhanced reserve will support the planned release of a feasibility study in the June quarter, with start of production slated for early 2025.

Donald is an advanced, globally significant critical minerals venture in the Wimmera district, 300 kilometres northwest of Melbourne and close to the town of Donald.

The new JORC-compliant proved and probable reserve totals 309 million tonnes grading 4.4% total heavy minerals for 13.6Mt  of heavy minerals. It includes a proved component, which is the highest possible confidence classification, of 263Mt at 4.4% heavy minerals.

Overall, the heavy mineral content has increased 32% to 13.6Mt compared to the previous 2001 estimate. Zircon content has increased by 15% to 2.2Mt.

Within the new reserve, contained rare earth minerals of monazite and xenotime have increased by 71% to 334,500t – reflecting a 25% increase in monazite and – for the first time – the addition of 89,700t of xenotime.

Monazite contains the light rare earth elements of neodymium and praseodymium, while xenotime hosts the heavy rare elements of dysprosium and terbium.

Mineral resource even larger

Astron noted the reserve only small component of the much larger mineral resource for Donald, which amounts to 2.634Bt at 4.6% heavy mineral.

This resource has 22.1Mt of contained zircon and is estimated to support a 40-year plus operation.

Contained monazite is 378,000t, while xenotime is 136,000t.

Critical minerals

While they sound exotic, these valuable materials have myriad industrial applications, including in co-called ‘super magnet’ rare earths used in electric vehicles and wind turbines, as well as mobile phones and for military uses.

Selling for more than US$3,000 per kilogram, terbium is used in applications including low energy lightbulbs and medical X-rays, while dysprosium is used in magnets and nuclear reactors.

Zircon, meanwhile, has widespread uses in ceramics, glass, chemicals and as a heat-resistant lining for furnaces.

Astron is modelling a 7.5Mtpa phase one mining operation base on simple ‘truck and shovel’ open cut methods.

The company aims to generate a heavy mineral concentrate and a rare earth element concentrate.

Because of the size of the project, it is planned to be developed “in a phased manner with consideration to market supply demand characteristics and to maximise capital efficiency.”

Output is expected to be 285,000 tonnes of heavy metal content and 9000 tonnes of rare earth element concentrates per annum, over the first five years of the phase one stage.

The total mine life is expected to be 43 years, with first production in late 2025.

The deposit was discovered by CRA (now Rio Tinto) in the mid 1980s and was acquired by Astron in 2004.

Astron’s expansion work since then has confirmed the project as “one of the world’s largest undeveloped zircon resources and one of the world’s most significant rare earth resources.”

Behind-the-scenes activity is already well advanced, including pilot metallurgical test work, obtaining a mining licence and concluding an Environmental Effects Statement to meet Victorian Government requirements.