Harmony says bond could help fund Wafi-Golpu

It also cautioned that while initial indications show the cost of the development, which it shares with Australian partner Newcrest Mining, will be $3bn, it remained "far too early" to give a final price tag.

In e-mailed responses to questions submitted by Reuters, Harmony confirmed reports that it was considering a bond to help finance its share of the project.

"Various financing options to fund our share of Wafi-Golpu exist given Harmony's strong balance sheet in South Africa," Harmony spokesperson Marian van der Walt said.

These included commercial debt or bond, cash generated from their South African assets, or commodity-backed financing on copper.

The costs of the project have been pegged at $3bn and when asked if those costs would rise or fall, Harmony said: "The pre-feasibility study will only be completed towards the end of December 2011 and it is therefore far too early to estimate exactly what the cost will be."

In a recent analysts' presentation, Harmony, the world's fifth-largest gold miner, said Wafi-Golpu might yield 300 000 to 700 000 ounces of gold a year or 200 000 to 320 000 metric tonnes of copper - both wide ranges.

The prospects there and a research note that suggested Harmony could be a ripe takeover target - which the company has dismissed and some analysts have said was pure speculation - have helped propel its share price to two-year highs.