Obuasi, Ghana

Obuasi, an underground operation mining to a depth of 1,500m, is located in Ghana’s Ashanti region, approximately 60km south of Kumasi.

Ownership

100%

Mineral ResERVE

6.75Moz
of gold

Gold production

221,000oz

All-in sustaining cost

$1,942/oz

Capital expenditure

$202m

Workforce

5,595

As at the year ended 31 December 2024

Overview and locality

Obuasi is an underground operation with the main accesses into the mine consisting of shafts and a single access decline with interlevel development of between 15 and 30m. The Obuasi Deeps Decline, which is situated at the southern end of the mine, is designed to extend to a depth of about 1,500m.

Existing infrastructure includes a 2.4Mtpa processing plant with flotation and bacterial oxidation (BIOX), underground development, hoisting shafts and associated infrastructure, power and water reticulation, office complexes, workshops and company housing estates. Power is supplied to the mine by the Volta River Authority and GridCo.

A brief history

Production at Obuasi started in 1897 and stopped in the last quarter of 2014. Some aspects of the mine continued under limited operational conditions, including the development of the underground decline
A favourable feasibility study was completed in 2017 and indicated a strong technical and economic case with an anticipated 20-year LOM
In 2018, approval was received from the AngloGold Ashanti Board to proceed with the project.
The redevelopment project began in early 2019 and first gold was poured during the fourth quarter of that year:
- Phase 1 of the redevelopment project was completed by end September 2020 and began commercial production on 1 October 2020
- Phase 2, construction and mine development, was completed in 2021 – together with phase 1 this brought capacity to 4,000t a day
- Phase 3, to develop the infrastructure necessary to support the planned ramp up in production to 5,000tpd, was completed at the end of 2024
The trial of the underhand drift and fill (UHDF) mining method in high-grade areas initiated in 2023 was successfully completed
As a result of difficult ground conditions encountered in high-grade areas during 2024, a hybrid mining approach was adopted in 2024. This hybrid approach uses sub-level open stopes (SLOS) in lower-grade areas and UHDF in higher-grade areas to deliver a safer, more predictable ramp-up profile