GEMCO is a manganese mining operation located in the Northern Territory, Australia. South32 owns 60 per cent of GEMCO and Anglo American Plc holds the remaining 40 per cent.

GEMCO is one of the largest and lowest-cost manganese ore producers in the world. Its attributes include high-grade ore, open-cut mining operations, its own port facilities located at Milner Bay only 16km from mining operations, and its close proximity to Asian export markets. GEMCO, whose FY2014 production of manganese ore was 4,776 kt (100 per cent basis), has a reserve life of 11 years.

South32 is in the early stages of assessing projects which have the potential to improve efficiency at GEMCO’s operations and is exploring areas which have the potential to extend the GEMCO mine life.


GEMCO commenced mining at Groote Eylandt in 1964, under BHP ownership. A crushing and wet screening plant was subsequently commissioned.

The benefication plant was commissioned in 1972 at a 1.0 Mtpa capacity (100 per cent basis) and has since undergone a series of expansions. The most recent of these expansions was the GEMCO expansion project, which was completed in 2013 and increased GEMCO’s capacity from 4.2 Mtpa to 4.8 Mtpa (100 per cent basis) through the introduction of a dense media circuit by-pass facility. The expansion also addressed key infrastructure constraints by increasing road and port capacity to 5.9 Mtpa (100 per cent basis), creating 1.1 Mtpa of additional infrastructure capacity for future expansions.

The US$139 million Premium Concentrate Project (PC02), was approved in August 2014 and is now in the early stage of execution. PC02 is expected to be complete by the end of FY2016 and ramp up to full production of 0.5 Mtpa in FY2017, thereby increasing GEMCO’s capacity from 4.8 Mtpa to 5.3 Mtpa (100 per cent basis).

This capacity expansion will be achieved by the construction of a standalone processing facility near the existing concentrator to produce a premium concentrate product for export sale. The expansion also involves an update to port infrastructure to handle the blending of premium concentrate with existing ore fines products.