South Africa's FirstRand and AngloGold Ashanti said on Tuesday they had sold their respective 50 percent stakes in Nufcor, the sole marketing agent for all uranium produced in the country, to a unit of U.S.-based utility Constellation Energy .

Nufcor International was a joint venture between AngloGold and banking group FirstRand, and was also the sole marketing agent for all uranium from South African miners and Canadian miner Uranium One .

Constellation Energy's subsidiary, Constellation Energy Commodities Group Ltd, now owns 100 percent of the shares of Nufcor, having emerged as a leading contender for the stakes held by FirstRand and AngloGold.

RMB , an associate of banking group FirstRand, said it sold its stake as Nufcor was not part of its core business, while AngloGold said it would still receive the services of Nufcor through an agency agreement.

The firms did not disclose financial details of the deals.

As one of the leading nuclear power plant owners in the United States, Constellation's acquisition is significant as it could trigger a trend where utilities start to trade uranium as a commodity, analysts have said.

Nufcor was not a core business of RMB and it therefore made sense to dispose of our shareholding in the company, RMB said.

RMB has, over a number of years, supported the development of Nufcor International into a valuable participant in the nuclear fuels market and was able to take advantage of the current interest in the sector to dispose of its investment.

Nufcor International is the marketing agent for uranium from South Africa, through an agreement with AngloGold's fully-owned uranium unit Nuclear Fuels Corp of South Africa (Nufcor SA).

AngloGold Ashanti will continue to receive the services of Nufcor through an agency agreement, the world's third biggest gold producer said in a statement. (Reporting by James Macharia; Editing by Paul Bolding)

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