Guinea-focused bauxite miner Alufer will produce 5 million tonnes of bauxite next year, the mines minister said on Monday, potentially boosting Guinea's output by more than a quarter.

Guinea holds nearly a third of the world's reserves of bauxite, the metal used to make aluminium, and currently produces around 18 million tonnes. Some mining investment has been held up due to a global commodity price slump.

"Alufer will produce 5 million tonnes of bauxite from 2017 for an estimated cost of $140 million," said mines and geology minister Abdoulaye Magassouba at an event marking the signing of a convention between Guinea and Alufer.

The independent miner, whose main Bel Air open-pit mine is located near the West African country's Atlantic coast, is set to eventually ramp up production to 10 million tonnes, Magassouba added.

Bauxite production at the site was originally due to begin this year but was held up due to contract negotiations. Alufer also has a mining permit in the Labe District in the centre of the country.