Open pit, carbonatite-hosted · Lynas Rare Earths
Mount Weld rare earth mine, Western Australia
Mount Weld in Western Australia holds ore reserves of 32.0 million tonnes at 6.44% TREO and mineral resources of 106.6 million tonnes at 4.12% TREO (4.39 million tonnes contained), as of 30 June 2024, supporting more than 20 years at the expanded 12,000 tonne-per-year NdPr rate.
From operator reserve statements · reviewed 28 October 2026
Mount Weld reserves and resources
| Category | Tonnage (million tonnes) | Grade (% TREO) | Contained TREO (thousand tonnes) |
|---|---|---|---|
| Measured | 20.0 | 7.2 | 1,435 |
| Indicated | 15.5 | 4.3 | 660 |
| Inferred | 71.1 | 3.2 | 2,295 |
| Total resource | 106.6 | 4.1 | 4,389 |
| Ore reserve | 32.0 | 6.44 | not stated |
Mineral resource at 30 June 2024 with a 2.5% TREO cut-off. Ore reserve cut-off 2.8% TREO against 4.0% in 2018. Totals may not balance due to rounding. TREO includes yttrium. A newer statement may exist; check the ASX announcements.
Mount Weld key facts
| Fact | Value |
|---|---|
| Location | Western Australia, Australia |
| Operator | Lynas Rare Earths (ASX: LYC) |
| Reporting standard | JORC 2012 |
| Drilling since 2018 update | Over 84,000 metres |
| Mine life, 7,200 tpa NdPr | More than 35 years |
| Mine life, 12,000 tpa NdPr (expansion) | More than 20 years |
| Dysprosium in reserves | Contained dysprosium oxide up 92% from 2018; all heavy rare earth grades, including terbium, now reported |
| Stored tailings | Added to the ore reserve; the expansion has fine grinding to recover historical coarse losses |
| Power | Hybrid renewable station; above the 70% target with 90% average renewable content in the June 2026 quarter |
Mount Weld in context
Resource growth since 2018
Mineral resources rose 92% from 55.4 million to 106.6 million tonnes and contained TREO rose 46% from 3.0 million to 4.39 million tonnes between the August 2018 and June 2024 estimates. Ore reserves rose 63% from 19.7 million to 32.0 million tonnes. The reserve cut-off was lowered from 4.0% to 2.8% TREO, which widens the ore included.
Expansion and recent operations
In the June 2026 quarter, Lynas reported that the only construction remaining on the Mt Weld expansion was additional tailings storage and that all equipment was operating except a new fine grinding mill, due in Q1 FY27. The company cited problems with the new water recycling plant, now resolved, and a variation in ore plus a fixed crusher replacing a movable one, which affected concentrate quality in the quarter.
Operator profile: Lynas Rare Earths. Other mines: rare earth mines. Reserves by country: reserves and production.
Mount Weld: frequently asked questions
How large is Mount Weld?
The 2024 estimate is 106.6 million tonnes at 4.12% TREO for 4.39 million tonnes of contained TREO, with ore reserves of 32.0 million tonnes at 6.44% TREO.
How long is the Mount Weld mine life?
More than 20 years at the expanded 12,000 tonne-per-year NdPr production capacity and more than 35 years at 7,200 tonnes per year (Lynas, August 2024).
Does Mount Weld contain heavy rare earths?
Yes. The 2024 reserve statement reports all heavy rare earth grades including terbium, and contained dysprosium oxide in reserves rose 92% from 2018.
Sources
Information only, not investment advice. Reviewed 28 October 2026.