Project life revenue by stream
- GoldA$1.94B40%
- CopperA$1.71B36%
- BismuthA$595M12%
- MagnetiteA$331M7%
- CobaltA$234M5%
Rover 1
The flagship: gold and critical minerals from one deposit.
Rover 1 is a high-grade IOCG deposit 57 km from Tennant Creek. The 2026 Scoping Study models a two-stage development — a 750,000 tpa underground operation producing gold doré, 99% copper, bismuth, cobalt and magnetite, refined downstream at Middle Arm in Darwin — over an 11-year initial mine life.
August 2026 study
What the 2026 Scoping Study concluded.
The 2026 Scoping Study lifts Rover 1 from the 500 ktpa plan of the 2022 PFS to a 750 ktpa steady-state operation over an 11-year initial mine life, with roughly ten years of steady-state production from 2030 to 2039.
- Rover 1 NPV, pre-tax
- A$1.08B
- Total project revenues
- A$4.81B
- Pre-tax IRR
- 56.3%
8% discount rate
Life of mine
Base case
- Post-tax NPV @ 8%
- A$682.8M
- Underlying mine profit
- A$2,070.4M
- Payback period
- 1 yr 7 mths
- Pre-production capital
- A$171.6M
- Steady-state rate
- 750 ktpa
- Initial mine life
- 11 yrs
Base case
Life of mine
From first capital deployment
Total, before first ore
Up from 500 ktpa in the 2022 PFS
≈ 10 yrs steady state, 2030–2039
See all study metrics
- Total material extracted and processed
- 7.27 Mt
- Gold revenue (life of mine)
- A$1,935.2M
- Copper revenue (life of mine)
- A$1,711.5M
- Bismuth revenue (life of mine)
- A$595.2M
- Magnetite revenue (life of mine)
- A$330.7M
- Cobalt revenue (life of mine)
- A$233.9M
- Total revenue (life of mine)
- A$4,806.5M
- Project operating costs
- A$1,953.8M
- Project cash flow
- A$1,941.4M
- NT Government and other royalties
- A$305.3M
- Pre-production capital cost
- A$171.6M
- Sustaining capital cost
- A$395.2M
- Underlying mine profit
- A$2,070.4M
- Pre-tax NPV @ 8%
- A$1,077.1M
- Pre-tax Internal Rate of Return (IRR)
- 56.3%
- Post-tax NPV @ 8%
- A$682.8M
- Payback period
- 1 year, 7 months
- Steady-state production rate
- 750 ktpa (from 500 ktpa in the 2022 PFS)
- Initial mine life
- 11 years, including construction and ramp-up
Source: 2026 Rover 1 Scoping Study, ASX:CST, August 2026 · Mineral Resource update, ASX:CST, 20 October 2025.
Revenue streams
Five products from one orebody.
Downstream products
Finished on Australian soil.
- Gold doré, refined to finished form in Australia.
- 99% copper, produced at the Middle Arm precinct, Darwin.
- 99% cobalt, alongside the copper stream.
- 96.5% magnetite as a saleable product.
- Bismuth concentrate, with China currently producing 83% of global 4N supply.
| Metal | Grade | Contained metal |
|---|---|---|
| Gold | 1.32 g/t Au | 305,500 oz |
| Copper | 1.05% Cu | 76,400 t |
| Bismuth | 0.11% Bi | 8,000 t |
| Cobalt | 0.06% Co | 4,400 t |
| Magnetite | 22.9% Fe₃O₄ | 1,667.3 kt |
Source: 2026 Rover 1 Scoping Study, ASX:CST, August 2026 · Mineral Resource update, ASX:CST, 20 October 2025.
Mine to metal
Beneficiate at Tennant Creek, refine in Darwin.
Ore is beneficiated at Rover 1 to a concentrate, then refined downstream at the Middle Arm Sustainable Development Precinct in Darwin. The NT Government awarded the project Major Project Status in April 2023, with land allocated at Middle Arm.
The route to market runs on existing infrastructure: the Tennant Creek commercial airport, the Adelaide–Darwin railway, the Stuart Highway and the Amadeus gas pipeline all sit near the project.
Geology
Jupiter and the broader Rover 1 system.
Rover 1 is an IOCG polymetallic deposit. The October 2025 Mineral Resource update lifted the JORC Mineral Resource 41% to 7.86 Mt, and the 2020 drilling season materially improved the understanding of higher-grade gold zones within the Jupiter lode and related structures.
The reinterpretation indicates Jupiter Deeps may be the depth extension of Jupiter West and continue through to the Ganymede intercepts.
Project video
A four-minute walk through the case.
Recorded after the 2022 PFS, the video walks through the mining and processing design and the downstream product strategy. The fundamentals are unchanged; the 2026 Scoping Study lifts throughput to 750 ktpa and adds the bismuth case.
2020 drill program
Bonanza intercepts in the Jupiter lode.
- 30.4m at 35.6 g/t Au and 1.46% Cu in Hole 20CRD001 reshaped Castile's view of the gold zone within the Jupiter lode.
- The 2020 drilling program highlighted high-grade bonanza gold zones similar to the super-rich lenses historically mined in the Tennant Creek goldfields.
- Data from the 2020 season supported a reinterpretation of fluid pathways: Jupiter Deeps may extend through Jupiter West to the Ganymede intercepts.
Keep going
Where to next.
The wider field
Rover Project district
Rover 1 sits within 1,054 km² of 100%-owned tenure over the Rover Mineral Field, with Explorer 108, Explorer 142 and more than 40 untested targets.
Open the Rover Project Stay currentASX announcements
The study release, the Mineral Resource update and every announcement since — as lodged with the ASX.
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