Ridge Mining may sell a stake in its $700m Sheba's Ridge nickel and platinum project to Zijin Mining, the Chinese firm which owns about 20% of the UK firm's listed shares.

In terms of a joint venture agreement on the project, Ridge Mining can increase its stake while partner, Anglo Platinum, would see its stake diminish to 12.5%. "I can't speak for Anglo, but I imagine this is not their kind of investment," said Donald McAlister, finance director. "If they [Zijin] could bring some cheap capital to the project, we'd be interested in giving them some of our shares [in the project] as well".

Ridge Mining is also considering enlisting a partner to build smelting and refining facilities at Sheba's Ridge, estimated to cost $200m, about a third of the total capital required. McAlister said there had been exploratory talks with African Rainbow Minerals (ARM), a Johannesburg-listed empowerment firm, and Toronto's LionOre Mining International.

"We are looking at options for the smelting as well as different technologies," said McAlister. "We have talked to LionOre about its Activox. We haven't closed the door on anything."

"There is no smelter large enough at the moment for the size of nickel concentrate Sheba's Ridge will be producing".

LionOre Mining and ARM are building a 20,000 to 25,000 tonnes/year smelting and refining facility for their Nkomati Nickel development using Activox, a type of hydrometallurgy that is much cheaper than conventional smelting technology and able to treat low grade concentrate.

Nkomati Nickel currently produces about 5,000 tonnes/year of nickel. It is also pressing ahead with plans to mine chrome which overlays additional nickel resources at the mine.

Sheba's Ridge is slated in its prefeasibility study to produce 24,000 tonnes/year of nickel, and copper and platinum group metals as by-products.

The project is profitable at about $4,50/lb against current – very high – nickel prices of $20/lb. "The long-term forecast on the nickel price is somewhere around $0.50c to $1/lb higher – $5.50/lb" said McAlister.

In its full-year financial results to end-December, Ridge Mining said development of the R1.3bn Blue Ridge platinum project had begun. Blue Ridge is expected to produce 125,000 oz of platinum group elements. However, the recent increase in the price of ruthenium and iridium added another 25,000 oz of concentrate. Ruthenium production alone would be worth revenue of an extra $10m/year, said Ridge Mining.

Ridge, which owns 50% of the relatively small Blue Ridge platinum mine, would predominantly become a nickel producer on completion of Sheba's Ridge. However, the growing importance of nickel, and the sale of non-core projects, did not mean a shift in commodity focus for Ridge.