Black Rock strides ahead with early works at giant Mahenge graphite project

• Black Rock Mining starts early works at Mahenge graphite project in Tanzania
• Company raised $10m in September 2025 to fund resettlement activities, plant earthworks and 220kv power line development
• Mahenge heading towards final investment decision once funding is finalised

Special Report: While most ASX graphite companies are still carrying out exploration or feasibility studies, Black Rock Mining has stolen a march on its peers with early works at its Mahenge project in Tanzania already underway.

The company celebrated this achievement with a formal groundbreaking ceremony that was officiated by Tanzanian Minister of Minerals Anthony Mavunde and attended by the South Korean ambassador and representatives of POSCO International.

It follows Black Rock Mining (ASX:BKT) raising $10 million through an equity placement in late September 2025 to fund the early works, which include completing resettlement activities, commencing plant site earthworks and advancing the crucial high voltage 220kv powerline from Ifakara to Mahenge.

This is aimed at completing sufficient works to support a rapid ramp-up of construction activity once the company is fully funded for Mahenge and pulls the trigger on the final investment decision.

Managing director John de Vries noted in late September 2025 that the start of early works reflected the series of milestones achieved recently by the company.

These include:

• The formalisation of offtake agreements in June 2024
• Appointment of Tanzanian based mining contractor, Taifa, in July 2024
• Formalisation of the POSCO International (POSCO) equity support agreement in September 2024
• Resolution of tax issues in March 2025
• Increased debt facilities in May 2025
• Completion of Implementation and Power Supply Agreements with TANESCO in May 2025

Mahenge graphite project

Black Rock’s start of early works is a testament to the appeal of its 324km2 Mahenge graphite project in Tanzania’s Ulanga district, about 250km north of the border with Mozambique and 250km west of the coastal port city of Mtwara on the Indian Ocean.

Mahenge has one of the largest flake graphite resources globally.

This “multi-generational” resource currently sits at 213Mt at 7.8% total graphitic carbon that includes an ore reserve of 70Mt at 8.5% TGC – the second largest of its kind in the world.

Under the feasibility study, the project’s Module 1 is current envisioned as being capable of producing 89,000tpa of 95-99% purity graphite concentrate using conventional flotation processing thanks to the low levels of deleterious impurities and favourable metallurgy.

Production will be ramped up to a steady state rate of 347,000tpa with the addition of another three modules.

This is expected to generate post-tax net present value and internal rate of return – both measures of profitability – of US$1.4bn and 36% respectively using a basket graphite price of US$1709/t and AISC of US$518/t, which sits in the first quartile for costs.

Capex for Module 1 and the Ifakara to Mahenge power line is estimated at about US$231m. This will increase by a further US$107m for Module 2, US$117m for Module 3 and US$104m for Module 4.

Initial operating life is estimated at 26 years.

The project benefits from potential access to key infrastructure, hydro-dominated and competitively priced grid power, rail, airstrip, water and dry stack tailings disposal.

Operations have been largely de-risked by two substantial pilot plant runs of 110t and the backing of the largest non-Chinese graphite anode producer POSCO.

POSCO has the future offtake rights for all graphite fines from Modules 1 and 2. It also has non-exclusive rights to market large flake graphite to buyers located outside of China.

Black Rock already has a US$204m facility agreement in place with the Development Bank of South Africa, Industrial Development Corporation of South Africa and CRDB Bank while POSCO has provided US$40m in funding via a share subscription and a further US$10m in pre-payments.

Early works

Black Rock notes that community compensation activities will be finalised with the completion of compensation payments for the access road, the last of the project areas that require the community to be compensated.

This will enable construction of the access road to commence once the FID is made.

The company is also working with Tanzania Electric Supply Company to start works relating to the high-voltage transmission line development.

Work to be completed during the early works program includes the survey works required for confirmation of route alignment and profile.

This will be used as a basis for transmission line design and tower spotting enabling tendering of contracts to commence.

This article was developed in collaboration with Black Rock Mining, a Stockhead advertiser at the time of publishing.

This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.