Zimbabwe Platinum Mines has announced plans to spend $46 million to dig deeper for platinum and other precious metals at its Ngezi mine.

The move will take about a year to complete and will be funded largely internally, with some outside input.

The transition will see the company dig around 960,000 tonnes of ore annually at the site, from around 240,000 tonnes at present, the company said in a statement.

Zimbabwe Platinum is moving away from mining open pit reserves at the mine, in southern Zimbabwe, in favour of richer underground reserves, as global metal prices continue to climb and demand for platinum increases.

The proposal is subject to approval by the Reserve Bank of Zimbabwe, according to the Reuters news agency.

Zimbabwe Platinum is 84.5 per cent owned by Impala Platinum Holdings (Implat) of South Africa.