SYDNEY (Bloomberg) — Bermuda-based Aquarius Platinum Ltd., a producer of the metal in South Africa and Zimbabwe, signed an initial accord to buy Ridge Mining Plc for A$156 million ($99 million) in shares to add resources and output.

Aquarius agreed to offer one share for every 2.75 Ridge shares, Aquarius said yesterday in a statement to the Australian stock exchange. The proposed offer is subject to "a number of pre-conditions", it said.

"Ridge will further diversify our portfolio, increase our resource base, add new production ounces and longevity to our production profile," Aquarius chief executive officer Stuart Murray said in the statement.

Aquarius rose eight percent to A$4.65 yesterday in Sydney trading. Ridge rose one percent to 54.5 pence in London trading, valuing the company at £49 million ($70 million). The shares rose 51 percent on February 12 after Ridge said talks were underway with Aquarius.

"The proposed combination offers Ridge shareholders the opportunity to retain the upside potential contained within our projects whilst reducing the risk inherent in a single early stage operation in a difficult economic environment," Ridge Mining chief executive Officer Terence Wilkinson said in the statement.