Gold, Copper and Critical Minerals in the NT

The Rover 1 Project

A high-grade IOCG deposit with five revenue streams.

Rover 1 is a high-grade Iron Oxide Copper Gold (IOCG) deposit beneath the Rover Mineral Field, 57 km from Tennant Creek.

The Rover 1 Scoping Study models an underground mine build with a modern 750,000 tpa processing plant focussed on the production of gold, copper, bismuth, cobalt and magnetite downstream products in Stage Two, and delivering robust operative and financial outcomes with an initial project life of 11 years.

At steady state the study models 750,000 tonnes of ore a year producing roughly 28,200 ounces of gold, 7,500 tonnes of copper, 500 tonnes of bismuth, 300 tonnes of cobalt and 110,500 tonnes of magnetite — around A$479.9M of revenue in an average year.

Stage One funds Stage Two: concentrate sales from Tennant Creek pay for the Darwin facility, so the downstream position is built out of the mine's own cash flow rather than a second raise.

Project life revenue by stream

• GoldA$1.94B40%
• CopperA$1.71B36%
• BismuthA$595M12%
• MagnetiteA$331M7%
• CobaltA$234M5%

Sources: “2026 Rover 1 Scoping Study Produces Outstanding Results”, ASX:CST, 20 August 2026 · Mineral Resource update, ASX:CST, 20 October 2025. A scoping study is a preliminary study; the cautionary statement that goes with these figures is on the Rover 1 page.

AustraliaThe Rover 1 Project

Why Castile

The investment case.

1. 01

   Advanced development project

   The 2026 Rover 1 Scoping Study is complete, and Rover 1 holds Major Project Status from the Northern Territory Government. A Bankable Feasibility Study is the next step.

2. 02

   Polymetallic exposure

   Gold and copper carry the project, with bismuth, cobalt and magnetite alongside — five revenue streams out of one orebody rather than a single-metal bet.

3. 03

   Downstream strategy

   Mining and beneficiation at Rover 1, with downstream processing proposed at Middle Arm in Darwin — funded from Stage One cash flow rather than a second raise.

4. 04

   Exploration upside

   Rover 1 sits within roughly 1,054 km² of the Rover Mineral Field, alongside the Explorer 108 and Explorer 142 resources. The orebody is open at depth and to the east.

1. Dec 2022

   Pre-Feasibility Study complete

   Rover 1 modelled as a 500 ktpa underground operation.

2. Apr 2024

   Major Project Status

   Awarded by the NT Government, with land allocated at Middle Arm in Darwin.

3. Oct 2025

   41% Mineral Resource uplift

   Updated JORC Mineral Resource of 7.86 Mt.

4. Feb 2026

   A$8.4M placement

   Raised to advance Rover 1 toward development.

5. Aug 2026

   2026 Rover 1 Scoping Study

   Rover 1 valued at A$1.08B NPV (8%) pre-tax over an 11-year initial mine life. Where the project stands today.

6. Next

   Bankable Feasibility Study

   Follows once final third-party cost estimates are signed off. No completion date has been guided.