Name of the Project
Kasiya rutile/graphite project.

Location
Central Malawi.

Project Owner/s
Sovereign Metals and Rio Tinto.

Rio Tinto invested in Sovereign in July 2023, resulting in an initial 15% shareholding and options, and expiring within 12 months of initial investment, to increase its position to 19.99%. Under the investment agreement, Rio Tinto will provide assistance and advice on technical and marketing aspects of Kasiya, including on Sovereign’s graphite co-product, with a primary focus on spherical purified graphite for the lithium-ion battery anode market.

Project Description
Kasiya is the biggest natural rutile deposit and second-largest flake graphite deposit in the world.

A prefeasibility study has confirmed a potentially major critical minerals project, with an extremely low carbon dioxide footprint delivering significant volumes of natural rutile and graphite while generating significant economic returns.

The proposed large-scale operation will process 24-million tonnes of ore a year to produce an estimated 245 000 t of natural rutile and 288 000 t of natural graphite a year at steady state, for an initial mine life of 25 years.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
The project has an after-tax net present value, at an 8% discount rate, of $1.61-billion and an internal rate of return of 28%, with a payback of 4.3 years from the start of production.

Capital Expenditure
Capital costs to first production are estimated at $597-million. Expansion capital is estimated at $287-million.

Planed Start/End Date
Not stated.

Latest Developments
Sovereign has reported “excellent” results from graphite testwork completed at four different laboratories, which all successfully produced high-grade graphite concentrate of between 94.9% and 97.8% total graphitic carbon (TGC) at high flotation recoveries of between 91.2% and 97.2%.

The graphite circuit feed provided for the laboratories, in Australia, Canada and South Africa, was produced at the company’s existing laboratory facility in Lilongwe, Malawi, where it was screened and separated over a wet shaking table.

The graphite feed grades of 3.5% to 4% TGC to the graphite circuit are significantly higher than the mineral resource grade of 1.44%, highlighting the 2.4- to 2.8-fold upgrading of graphite grades when run-of-mine (RoM) ore passes through the front-end rutile gravity separation circuit.

This demonstrates the ease of separating the rutile heavy mineral and graphite streams from the front end of the Kasiya prefeasibility study process flowsheet.

Subsequently, the two product streams pass into distinct, industry-standard, final product flowsheets. This further highlights the commercial benefits of having rutile and graphite mineralisation in the same soft saprolite-hosted orebody.

The first stage of upgrading the graphite feed, rougher flotation, achieved very high rejection of more than 90% of waste materials to rougher tails, producing a rougher concentrate of more than 55% TGC, and high recoveries of between 94% and 98% in laboratory-scale testing consistently across all four laboratories.

Upgrading the graphite feed at very high recoveries and rejection of nongraphitic minerals without RoM milling supports low-cost graphite production.

The rougher concentrate was further upgraded through laboratory-scale flotation, cleaning and polishing stages, producing high-grade concentrates at high graphite circuit recoveries.

Sovereign has reported that the Kasiya concentrates have very low levels of sulphur, iron, silicon and aluminium. Sulphur, in particular, can be difficult to remove in the purification processes required to produce anode materials.

Benchmarked against the Chinese standard, since China dominates the supply of graphite for battery anodes, Sovereign believes this could potentially lead to significant commercial advantages during purification, and Kasiya’s potential as a long-term secure source of graphite outside of China.

Kasiya concentrate has been sent for downstream testwork at graphite consultancy ProGraphite to produce and characterise coated spheronised purified graphite (CSPG) active anode material for lithium-ion batteries.

ProGraphite is conducting shaping, purification and coating testwork to produce CSPG and evaluate the electrochemical performance of Kasiya CSPG.

Sovereign has said this will provide baseline data for further optimisation and engagement with offtakers. Initial outcomes of this testwork are expected to be released in the coming weeks.

Key Contracts, Suppliers, and Consultants
SocialEssence (continued development of Sovereign’s stakeholder relations, social performance objectives and its CSR framework).

Contact Details for Project Information
Sovereign Metals, Tel +61 8 9322 6322, or email info@sovereignmetals.com.au.